diff --git a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JavaTypeTransformer.java b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JavaTypeTransformer.java
index 1bfaef40a7e..27ddb5b3fd0 100644
--- a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JavaTypeTransformer.java
+++ b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JavaTypeTransformer.java
@@ -148,7 +148,7 @@ public class JavaTypeTransformer {
                 }
                 else {
                     // 'L extends List<T>' in Java is a List<T> in Kotlin, not a List<T?>
-                    boolean nullable = !EnumSet.of(SUPERTYPE_ARGUMENT, SUPERTYPE).contains(howThisTypeIsUsed);
+                    boolean nullable = !EnumSet.of(TYPE_ARGUMENT, SUPERTYPE_ARGUMENT, SUPERTYPE).contains(howThisTypeIsUsed);
 
                     ClassDescriptor classData = JavaToKotlinClassMap.getInstance().mapKotlinClass(new FqName(psiClass.getQualifiedName()),
                                                                                                     howThisTypeIsUsed);
@@ -228,16 +228,24 @@ public class JavaTypeTransformer {
                         return TypeUtils.makeNullable(jetType);
                 }
 
+                boolean vararg = arrayType instanceof PsiEllipsisType;
+
+                Variance projectionKind = arrayElementTypeProjectionKind(vararg);
+                TypeUsage howArgumentTypeIsUsed = vararg ? MEMBER_SIGNATURE_CONTRAVARIANT : TYPE_ARGUMENT;
+
+                JetType type = transformToType(componentType, howArgumentTypeIsUsed, typeVariableResolver);
+                return TypeUtils.makeNullable(KotlinBuiltIns.getInstance().getArrayType(projectionKind, type));
+            }
+
+            private Variance arrayElementTypeProjectionKind(boolean vararg) {
                 Variance variance;
-                if (howThisTypeIsUsed == MEMBER_SIGNATURE_CONTRAVARIANT && !(arrayType instanceof PsiEllipsisType)) {
+                if (howThisTypeIsUsed == MEMBER_SIGNATURE_CONTRAVARIANT && !vararg) {
                     variance = Variance.OUT_VARIANCE;
                 }
                 else {
                     variance = Variance.INVARIANT;
                 }
-
-                JetType type = transformToType(componentType, typeVariableResolver);
-                return TypeUtils.makeNullable(KotlinBuiltIns.getInstance().getArrayType(variance, type));
+                return variance;
             }
 
             @Override
diff --git a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/AlternativeMethodSignatureData.java b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/AlternativeMethodSignatureData.java
index e74d6f6aa84..d9463e67ea7 100644
--- a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/AlternativeMethodSignatureData.java
+++ b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/AlternativeMethodSignatureData.java
@@ -29,7 +29,10 @@ import org.jetbrains.jet.lang.psi.*;
 import org.jetbrains.jet.lang.resolve.java.JavaDescriptorResolver;
 import org.jetbrains.jet.lang.resolve.java.wrapper.PsiMethodWrapper;
 import org.jetbrains.jet.lang.resolve.name.Name;
-import org.jetbrains.jet.lang.types.*;
+import org.jetbrains.jet.lang.types.JetType;
+import org.jetbrains.jet.lang.types.TypeSubstitutor;
+import org.jetbrains.jet.lang.types.TypeUtils;
+import org.jetbrains.jet.lang.types.Variance;
 import org.jetbrains.jet.lang.types.checker.JetTypeChecker;
 import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
 
@@ -37,6 +40,9 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
+import static org.jetbrains.jet.lang.resolve.java.JavaTypeTransformer.TypeUsage.MEMBER_SIGNATURE_CONTRAVARIANT;
+import static org.jetbrains.jet.lang.resolve.java.JavaTypeTransformer.TypeUsage.UPPER_BOUND;
+
 /**
  * @author Evgeny Gerashchenko
  * @since 6/5/12
@@ -181,7 +187,7 @@ public class AlternativeMethodSignatureData extends ElementAlternativeSignatureD
                     throw new AlternativeSignatureMismatchException("Parameter in method signature is not vararg, but in alternative signature it is vararg");
                 }
 
-                alternativeType = TypeTransformingVisitor.computeType(alternativeTypeElement, originalParameterDescriptor.getType(), originalToAltTypeParameters);
+                alternativeType = TypeTransformingVisitor.computeType(alternativeTypeElement, originalParameterDescriptor.getType(), originalToAltTypeParameters, MEMBER_SIGNATURE_CONTRAVARIANT);
                 alternativeVarargElementType = null;
             }
             else {
@@ -190,7 +196,7 @@ public class AlternativeMethodSignatureData extends ElementAlternativeSignatureD
                 }
 
                 alternativeVarargElementType = TypeTransformingVisitor.computeType(alternativeTypeElement, originalParamVarargElementType,
-                                                                                   originalToAltTypeParameters);
+                                                                                   originalToAltTypeParameters, MEMBER_SIGNATURE_CONTRAVARIANT);
                 alternativeType = KotlinBuiltIns.getInstance().getArrayType(alternativeVarargElementType);
             }
 
@@ -255,7 +261,7 @@ public class AlternativeMethodSignatureData extends ElementAlternativeSignatureD
                 assert (altTypeElement != null);
 
                 altParamDescriptor.addUpperBound(TypeTransformingVisitor.computeType(altTypeElement, upperBound,
-                                                                                     originalToAltTypeParameters));
+                                                                                     originalToAltTypeParameters, UPPER_BOUND));
                 upperBoundIndex++;
             }
 
diff --git a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/ElementAlternativeSignatureData.java b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/ElementAlternativeSignatureData.java
index 6002da94dfa..8367749fea7 100644
--- a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/ElementAlternativeSignatureData.java
+++ b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/ElementAlternativeSignatureData.java
@@ -32,6 +32,8 @@ import org.jetbrains.jet.resolve.DescriptorRenderer;
 import java.util.List;
 import java.util.Map;
 
+import static org.jetbrains.jet.lang.resolve.java.JavaTypeTransformer.TypeUsage.MEMBER_SIGNATURE_COVARIANT;
+
 public abstract class ElementAlternativeSignatureData {
     private String error;
     private boolean isAnnotated;
@@ -102,6 +104,6 @@ public abstract class ElementAlternativeSignatureData {
         JetTypeElement typeElement = altReturnTypeReference.getTypeElement();
         assert (typeElement != null);
 
-        return TypeTransformingVisitor.computeType(typeElement, originalType, originalToAltTypeParameters);
+        return TypeTransformingVisitor.computeType(typeElement, originalType, originalToAltTypeParameters, MEMBER_SIGNATURE_COVARIANT);
     }
 }
diff --git a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/TypeTransformingVisitor.java b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/TypeTransformingVisitor.java
index 38ebcb60e14..da59349d597 100644
--- a/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/TypeTransformingVisitor.java
+++ b/compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/kotlinSignature/TypeTransformingVisitor.java
@@ -26,6 +26,7 @@ import org.jetbrains.jet.lang.descriptors.TypeParameterDescriptorImpl;
 import org.jetbrains.jet.lang.psi.*;
 import org.jetbrains.jet.lang.resolve.DescriptorUtils;
 import org.jetbrains.jet.lang.resolve.java.JavaToKotlinClassMap;
+import org.jetbrains.jet.lang.resolve.java.JavaTypeTransformer;
 import org.jetbrains.jet.lang.resolve.java.JvmClassName;
 import org.jetbrains.jet.lang.resolve.java.KotlinToJavaTypesMap;
 import org.jetbrains.jet.lang.resolve.scopes.JetScope;
@@ -35,15 +36,21 @@ import org.jetbrains.jet.resolve.DescriptorRenderer;
 
 import java.util.*;
 
+import static org.jetbrains.jet.lang.resolve.java.JavaTypeTransformer.TypeUsage.*;
+
 class TypeTransformingVisitor extends JetVisitor<JetType, Void> {
     private final JetType originalType;
     private final Map<TypeParameterDescriptor, TypeParameterDescriptorImpl> originalToAltTypeParameters;
 
+    private final JavaTypeTransformer.TypeUsage typeUsage;
+
     private TypeTransformingVisitor(
             JetType originalType,
-            Map<TypeParameterDescriptor, TypeParameterDescriptorImpl> originalToAltTypeParameters
+            Map<TypeParameterDescriptor, TypeParameterDescriptorImpl> originalToAltTypeParameters,
+            JavaTypeTransformer.TypeUsage typeUsage
     ) {
         this.originalType = originalType;
+        this.typeUsage = typeUsage;
         this.originalToAltTypeParameters = Collections.unmodifiableMap(originalToAltTypeParameters);
     }
 
@@ -51,20 +58,21 @@ class TypeTransformingVisitor extends JetVisitor<JetType, Void> {
     public static JetType computeType(
             @NotNull JetTypeElement alternativeTypeElement,
             @NotNull JetType originalType,
-            @NotNull Map<TypeParameterDescriptor, TypeParameterDescriptorImpl> originalToAltTypeParameters
+            @NotNull Map<TypeParameterDescriptor, TypeParameterDescriptorImpl> originalToAltTypeParameters,
+            @NotNull JavaTypeTransformer.TypeUsage typeUsage
     ) {
-        JetType computedType = alternativeTypeElement.accept(new TypeTransformingVisitor(originalType, originalToAltTypeParameters), null);
+        JetType computedType = alternativeTypeElement.accept(new TypeTransformingVisitor(originalType, originalToAltTypeParameters, typeUsage), null);
         assert (computedType != null);
         return computedType;
     }
 
     @Override
     public JetType visitNullableType(JetNullableType nullableType, Void aVoid) {
-        if (!originalType.isNullable()) {
+        if (!originalType.isNullable() && typeUsage != TYPE_ARGUMENT) {
             throw new AlternativeSignatureMismatchException("Auto type '%s' is not-null, while type in alternative signature is nullable: '%s'",
                  DescriptorRenderer.TEXT.renderType(originalType), nullableType.getText());
         }
-        return TypeUtils.makeNullable(computeType(nullableType.getInnerType(), originalType, originalToAltTypeParameters));
+        return TypeUtils.makeNullable(computeType(nullableType.getInnerType(), originalType, originalToAltTypeParameters, typeUsage));
     }
 
     @Override
@@ -134,7 +142,7 @@ class TypeTransformingVisitor extends JetVisitor<JetType, Void> {
             assert argumentAlternativeTypeElement != null;
 
             TypeProjection argument = arguments.get(i);
-            JetType alternativeArgumentType = computeType(argumentAlternativeTypeElement, argument.getType(), originalToAltTypeParameters);
+            JetType alternativeArgumentType = computeType(argumentAlternativeTypeElement, argument.getType(), originalToAltTypeParameters, TYPE_ARGUMENT);
             Variance projectionKind = argument.getProjectionKind();
             Variance altProjectionKind;
             if (type instanceof JetUserType) {
diff --git a/compiler/testData/loadJava/ArrayTypeVariance.kt b/compiler/testData/loadJava/ArrayTypeVariance.kt
index 7883a32e19b..54089f097d4 100644
--- a/compiler/testData/loadJava/ArrayTypeVariance.kt
+++ b/compiler/testData/loadJava/ArrayTypeVariance.kt
@@ -1,7 +1,7 @@
 package test
 
 public class ArrayTypeVariance : java.lang.Object() {
-    public fun toArray(p0: Array<out Any?>?): Array<Any?>? {
+    public fun toArray(p0: Array<out Any>?): Array<Any>? {
         throw UnsupportedOperationException()
     }
 }
diff --git a/compiler/testData/loadJava/ArrayTypeVariance.txt b/compiler/testData/loadJava/ArrayTypeVariance.txt
index 5ff82f8222c..71f3a033fa4 100644
--- a/compiler/testData/loadJava/ArrayTypeVariance.txt
+++ b/compiler/testData/loadJava/ArrayTypeVariance.txt
@@ -2,5 +2,5 @@ namespace test
 
 public final class test.ArrayTypeVariance : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.ArrayTypeVariance
-    public final fun toArray(/*0*/ p0: jet.Array<out jet.Any?>?): jet.Array<jet.Any?>?
+    public final fun toArray(/*0*/ p0: jet.Array<out jet.Any>?): jet.Array<jet.Any>?
 }
diff --git a/compiler/testData/loadJava/FieldOfArrayType.kt b/compiler/testData/loadJava/FieldOfArrayType.kt
index 128ae0d364c..8b4d9da67bf 100644
--- a/compiler/testData/loadJava/FieldOfArrayType.kt
+++ b/compiler/testData/loadJava/FieldOfArrayType.kt
@@ -1,5 +1,5 @@
 package test
 
 public open class FieldOfArrayType() : java.lang.Object() {
-    public var files: Array<java.io.File?>? = null
+    public var files: Array<java.io.File>? = null
 }
diff --git a/compiler/testData/loadJava/FieldOfArrayType.txt b/compiler/testData/loadJava/FieldOfArrayType.txt
index f654bb68067..e354aa5d6da 100644
--- a/compiler/testData/loadJava/FieldOfArrayType.txt
+++ b/compiler/testData/loadJava/FieldOfArrayType.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.FieldOfArrayType : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.FieldOfArrayType
-    public final var files: jet.Array<java.io.File?>?
+    public final var files: jet.Array<java.io.File>?
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.kt b/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.kt
index 3ad5358f390..d3f47dca06b 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.kt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.kt
@@ -3,5 +3,5 @@ package test
 import java.util.*
 
 public open class WrongReturnTypeStructure : Object() {
-    public open fun foo(p0 : String?, p1 : List<Map.Entry<String?, String?>?>?) : String? = ""
+    public open fun foo(p0 : String?, p1 : List<Map.Entry<String, String>>?) : String? = ""
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.txt b/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.txt
index 633cb59ba14..4007600c3b9 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.txt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongReturnTypeStructure.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.WrongReturnTypeStructure : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.WrongReturnTypeStructure
-    public open fun foo(/*0*/ p0: jet.String?, /*1*/ p1: jet.List<jet.Map.Entry<jet.String?, jet.String?>?>?): jet.String?
+    public open fun foo(/*0*/ p0: jet.String?, /*1*/ p1: jet.List<jet.Map.Entry<jet.String, jet.String>>?): jet.String?
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.kt b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.kt
index 7ccbfb88025..71092227dbb 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.kt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.kt
@@ -3,6 +3,6 @@ package test
 import java.util.*
 
 public open class WrongTypeParameterBoundStructure1 : Object() {
-    public open fun <erased A, erased B : Runnable?> foo(p0 : A?, p1 : List<B>?) where B : List<Cloneable?>? {
+    public open fun <erased A, erased B : Runnable?> foo(p0 : A?, p1 : List<B>?) where B : List<Cloneable>? {
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.txt b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.txt
index 18bb06ded17..ed56414d418 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.txt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure1.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.WrongTypeParameterBoundStructure1 : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.WrongTypeParameterBoundStructure1
-    public open fun </*0*/ A : jet.Any?, /*1*/ B : java.lang.Runnable? & jet.List<java.lang.Cloneable?>?>foo(/*0*/ p0: A?, /*1*/ p1: jet.List<B>?): jet.Tuple0
+    public open fun </*0*/ A : jet.Any?, /*1*/ B : java.lang.Runnable? & jet.List<java.lang.Cloneable>?>foo(/*0*/ p0: A?, /*1*/ p1: jet.List<B>?): jet.Tuple0
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.java b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.java
index 6c2eaa4d461..54ff2850c6d 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.java
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.java
@@ -6,7 +6,7 @@ import jet.runtime.typeinfo.KotlinSignature;
 import org.jetbrains.jet.jvm.compiler.annotation.ExpectLoadError;
 
 public class WrongTypeParameterBoundStructure2 {
-    @ExpectLoadError("'jet.List<java.lang.Cloneable?>?' type in method signature has 1 type arguments, while 'List' in alternative signature has 0 of them")
+    @ExpectLoadError("'jet.List<java.lang.Cloneable>?' type in method signature has 1 type arguments, while 'List' in alternative signature has 0 of them")
     @KotlinSignature("fun <A, B : Runnable> foo(a : A, b : List<B>) where B : List")
     public <A, B extends Runnable & List<Cloneable>> void foo(A a, List<? extends B> b) {
     }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.kt b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.kt
index 4f8fff9623a..6d553796873 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.kt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.kt
@@ -3,6 +3,6 @@ package test
 import java.util.*
 
 public open class WrongTypeParameterBoundStructure2 : Object() {
-    public open fun <erased A, erased B : Runnable?> foo(p0 : A?, p1 : List<B>?) where B : List<Cloneable?>? {
+    public open fun <erased A, erased B : Runnable?> foo(p0 : A?, p1 : List<B>?) where B : List<Cloneable>? {
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.txt b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.txt
index 05d74d3f8f0..ffb26374e5d 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.txt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeParameterBoundStructure2.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.WrongTypeParameterBoundStructure2 : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.WrongTypeParameterBoundStructure2
-    public open fun </*0*/ A : jet.Any?, /*1*/ B : java.lang.Runnable? & jet.List<java.lang.Cloneable?>?>foo(/*0*/ p0: A?, /*1*/ p1: jet.List<B>?): jet.Tuple0
+    public open fun </*0*/ A : jet.Any?, /*1*/ B : java.lang.Runnable? & jet.List<java.lang.Cloneable>?>foo(/*0*/ p0: A?, /*1*/ p1: jet.List<B>?): jet.Tuple0
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.kt b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.kt
index dddca08bb88..adaf2fad6b2 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.kt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.kt
@@ -3,7 +3,7 @@ package test
 import java.util.*
 
 public open class WrongTypeVariance : Object() {
-    public open fun copy(p0 : Array<out Number?>?, p1 : Array<out Number?>?) : MutableList<Number?>? {
+    public open fun copy(p0 : Array<out Number>?, p1 : Array<out Number>?) : MutableList<Number>? {
         throw UnsupportedOperationException()
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.txt b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.txt
index b61cc9880f9..17c582864f3 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.txt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongTypeVariance.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.WrongTypeVariance : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.WrongTypeVariance
-    public open fun copy(/*0*/ p0: jet.Array<out jet.Number?>?, /*1*/ p1: jet.Array<out jet.Number?>?): jet.MutableList<jet.Number?>?
+    public open fun copy(/*0*/ p0: jet.Array<out jet.Number>?, /*1*/ p1: jet.Array<out jet.Number>?): jet.MutableList<jet.Number>?
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.kt b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.kt
index 72153127f18..70469869cf8 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.kt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.kt
@@ -3,5 +3,5 @@ package test
 import java.util.*
 
 public open class WrongValueParameterStructure1 : Object() {
-    public open fun foo(p0 : String?, p1 : List<Map.Entry<String?, String?>?>?) : String? = ""
+    public open fun foo(p0 : String?, p1 : List<Map.Entry<String, String>>?) : String? = ""
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.txt b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.txt
index 34118471c98..8a21da86b00 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.txt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure1.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.WrongValueParameterStructure1 : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.WrongValueParameterStructure1
-    public open fun foo(/*0*/ p0: jet.String?, /*1*/ p1: jet.List<jet.Map.Entry<jet.String?, jet.String?>?>?): jet.String?
+    public open fun foo(/*0*/ p0: jet.String?, /*1*/ p1: jet.List<jet.Map.Entry<jet.String, jet.String>>?): jet.String?
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.java b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.java
index 40b9f5a4fcb..ea74515befe 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.java
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.java
@@ -5,7 +5,7 @@ import jet.runtime.typeinfo.KotlinSignature;
 import org.jetbrains.jet.jvm.compiler.annotation.ExpectLoadError;
 
 public class WrongValueParameterStructure2 {
-    @ExpectLoadError("'jet.Map.Entry<jet.String?, jet.String?>?' type in method signature has 2 type arguments, while 'Map.Entry<String?>' in alternative signature has 1 of them")
+    @ExpectLoadError("'jet.Map.Entry<jet.String, jet.String>' type in method signature has 2 type arguments, while 'Map.Entry<String?>' in alternative signature has 1 of them")
     @KotlinSignature("fun foo(a : String, b : List<Map.Entry<String?>?>) : String")
     public String foo(String a, List<Map.Entry<String, String>> b) {
         throw new UnsupportedOperationException();
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.kt b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.kt
index 9a0e3b9c62c..5cf766dc255 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.kt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.kt
@@ -3,5 +3,5 @@ package test
 import java.util.*
 
 public open class WrongValueParameterStructure2 : Object() {
-    public open fun foo(p0 : String?, p1 : List<Map.Entry<String?, String?>?>?) : String? = ""
+    public open fun foo(p0 : String?, p1 : List<Map.Entry<String, String>>?) : String? = ""
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.txt b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.txt
index e45fe846a05..69d852d499f 100644
--- a/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.txt
+++ b/compiler/testData/loadJava/kotlinSignature/error/WrongValueParameterStructure2.txt
@@ -2,5 +2,5 @@ namespace test
 
 public open class test.WrongValueParameterStructure2 : java.lang.Object {
     public final /*constructor*/ fun <init>(): test.WrongValueParameterStructure2
-    public open fun foo(/*0*/ p0: jet.String?, /*1*/ p1: jet.List<jet.Map.Entry<jet.String?, jet.String?>?>?): jet.String?
+    public open fun foo(/*0*/ p0: jet.String?, /*1*/ p1: jet.List<jet.Map.Entry<jet.String, jet.String>>?): jet.String?
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.kt b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.kt
index 3947c5029c4..f3fde68291a 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.kt
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.kt
@@ -3,10 +3,10 @@ package test
 public trait InheritNotVararg: Object {
 
     public trait Super: Object {
-        public fun foo(p0: Array<out String?>?)
+        public fun foo(p0: Array<out String>?)
     }
 
     public trait Sub: Super {
-        override fun foo(p0: Array<out String?>?)
+        override fun foo(p0: Array<out String>?)
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.txt b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.txt
index 61e72c2a67d..60ae207c163 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.txt
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVararg.txt
@@ -2,9 +2,9 @@ namespace test
 
 public abstract trait test.InheritNotVararg : java.lang.Object {
     public abstract trait test.InheritNotVararg.Sub : test.InheritNotVararg.Super {
-        public abstract override /*1*/ fun foo(/*0*/ p0: jet.Array<out jet.String?>?): jet.Tuple0
+        public abstract override /*1*/ fun foo(/*0*/ p0: jet.Array<out jet.String>?): jet.Tuple0
     }
     public abstract trait test.InheritNotVararg.Super : java.lang.Object {
-        public abstract fun foo(/*0*/ p0: jet.Array<out jet.String?>?): jet.Tuple0
+        public abstract fun foo(/*0*/ p0: jet.Array<out jet.String>?): jet.Tuple0
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.kt b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.kt
index 44622b7f3d6..ae529346031 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.kt
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.kt
@@ -3,10 +3,10 @@ package test
 public trait InheritNotVarargInteger: Object {
 
     public trait Super: Object {
-        public fun foo(p0: Array<out Int?>?)
+        public fun foo(p0: Array<out Int>?)
     }
 
     public trait Sub: Super {
-        override fun foo(p0: Array<out Int?>?)
+        override fun foo(p0: Array<out Int>?)
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.txt b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.txt
index ea9d28c72fa..111a40931a9 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.txt
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/parameter/InheritNotVarargInteger.txt
@@ -2,9 +2,9 @@ namespace test
 
 public abstract trait test.InheritNotVarargInteger : java.lang.Object {
     public abstract trait test.InheritNotVarargInteger.Sub : test.InheritNotVarargInteger.Super {
-        public abstract override /*1*/ fun foo(/*0*/ p0: jet.Array<out jet.Int?>?): jet.Tuple0
+        public abstract override /*1*/ fun foo(/*0*/ p0: jet.Array<out jet.Int>?): jet.Tuple0
     }
     public abstract trait test.InheritNotVarargInteger.Super : java.lang.Object {
-        public abstract fun foo(/*0*/ p0: jet.Array<out jet.Int?>?): jet.Tuple0
+        public abstract fun foo(/*0*/ p0: jet.Array<out jet.Int>?): jet.Tuple0
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/return/AddNullabilitySameGenericType1.java b/compiler/testData/loadJava/kotlinSignature/propagation/return/AddNullabilitySameGenericType1.java
index 0ea9be382a8..6cd4db019bf 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/return/AddNullabilitySameGenericType1.java
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/return/AddNullabilitySameGenericType1.java
@@ -13,7 +13,7 @@ public interface AddNullabilitySameGenericType1 {
     }
 
     public interface Sub extends Super {
-        @ExpectLoadError("Auto type 'jet.String' is not-null, while type in alternative signature is nullable: 'String?'")
+        @ExpectLoadError("Return type is changed to not subtype for method which overrides another: MutableList<String?>, was: MutableList<String>")
         @KotlinSignature("fun foo(): MutableList<String?>")
         List<String> foo();
     }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.java b/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.java
index 4fd69a9c1af..0970c4e8810 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.java
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.java
@@ -9,7 +9,7 @@ public interface HalfSubstitutedTypeParameters {
     public interface TrickyList<X, E> extends List<E> {}
 
     public interface Super {
-        @KotlinSignature("fun foo(): MutableList<String>")
+        @KotlinSignature("fun foo(): MutableList<String?>")
         List<String> foo();
     }
 
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.kt b/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.kt
index 21853229e97..dc3bce94818 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.kt
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.kt
@@ -5,10 +5,10 @@ public trait HalfSubstitutedTypeParameters: Object {
     public trait TrickyList<X, E>: MutableList<E> {}
 
     public trait Super: Object {
-        public fun foo(): MutableList<String>
+        public fun foo(): MutableList<String?>
     }
 
     public trait Sub: Super {
-        override fun foo(): TrickyList<Int?, String>
+        override fun foo(): TrickyList<Int, String?>
     }
 }
diff --git a/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.txt b/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.txt
index 1b129935af4..873560d9138 100644
--- a/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.txt
+++ b/compiler/testData/loadJava/kotlinSignature/propagation/return/HalfSubstitutedTypeParameters.txt
@@ -2,10 +2,10 @@ namespace test
 
 public abstract trait test.HalfSubstitutedTypeParameters : java.lang.Object {
     public abstract trait test.HalfSubstitutedTypeParameters.Sub : test.HalfSubstitutedTypeParameters.Super {
-        public abstract override /*1*/ fun foo(): test.HalfSubstitutedTypeParameters.TrickyList<jet.Int?, jet.String>
+        public abstract override /*1*/ fun foo(): test.HalfSubstitutedTypeParameters.TrickyList<jet.Int, jet.String?>
     }
     public abstract trait test.HalfSubstitutedTypeParameters.Super : java.lang.Object {
-        public abstract fun foo(): jet.MutableList<jet.String>
+        public abstract fun foo(): jet.MutableList<jet.String?>
     }
     public abstract trait test.HalfSubstitutedTypeParameters.TrickyList</*0*/ X : jet.Any?, /*1*/ E : jet.Any?> : jet.MutableList<E> {
         public abstract override /*1*/ /*fake_override*/ fun add(/*0*/ e: E): jet.Boolean
diff --git a/compiler/tests/org/jetbrains/jet/jvm/compiler/AbstractLoadJavaTest.java b/compiler/tests/org/jetbrains/jet/jvm/compiler/AbstractLoadJavaTest.java
index 8738662d208..34035f63789 100644
--- a/compiler/tests/org/jetbrains/jet/jvm/compiler/AbstractLoadJavaTest.java
+++ b/compiler/tests/org/jetbrains/jet/jvm/compiler/AbstractLoadJavaTest.java
@@ -17,6 +17,7 @@
 package org.jetbrains.jet.jvm.compiler;
 
 import com.intellij.openapi.util.Pair;
+import junit.framework.ComparisonFailure;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.ConfigurationKind;
 import org.jetbrains.jet.lang.descriptors.NamespaceDescriptor;
@@ -51,8 +52,25 @@ public abstract class AbstractLoadJavaTest extends TestCaseWithTmpdir {
                 tmpdir, myTestRootDisposable, ConfigurationKind.JDK_AND_ANNOTATIONS);
         NamespaceDescriptor nsb = nsbAndBindingContext.first;
 
+        boolean fail = false;
+        try {
+            ExpectedLoadErrorsUtil.checkForLoadErrors(nsb, nsbAndBindingContext.second);
+        }
+        catch (ComparisonFailure e) {
+            // to let the next check run even if this one failed
+            System.err.println("Expected: " + e.getExpected());
+            System.err.println("Actual  : " + e.getActual());
+            e.printStackTrace();
+            fail = true;
+        }
+        catch (AssertionError e) {
+            e.printStackTrace();
+            fail = true;
+        }
 
         compareNamespaces(nsa, nsb, DONT_INCLUDE_METHODS_OF_OBJECT, txtFile);
-        ExpectedLoadErrorsUtil.checkForLoadErrors(nsb, nsbAndBindingContext.second);
+        if (fail) {
+            fail("See error above");
+        }
     }
 }
diff --git a/libraries/stdlib/src/kotlin/modules/ModuleBuilder.kt b/libraries/stdlib/src/kotlin/modules/ModuleBuilder.kt
index 7a9a85319ab..7c3032251d2 100644
--- a/libraries/stdlib/src/kotlin/modules/ModuleBuilder.kt
+++ b/libraries/stdlib/src/kotlin/modules/ModuleBuilder.kt
@@ -29,9 +29,9 @@ class AnnotationsPathBuilder(val parent: ModuleBuilder) {
 
 open class ModuleBuilder(val name: String): Module {
     // http://youtrack.jetbrains.net/issue/KT-904
-    private val sourceFiles0: ArrayList<String?> = ArrayList<String?>()
-    private val classpathRoots0: ArrayList<String?> = ArrayList<String?>()
-    private val annotationsRoots0: ArrayList<String?> = ArrayList<String?>()
+    private val sourceFiles0 = ArrayList<String>()
+    private val classpathRoots0 = ArrayList<String>()
+    private val annotationsRoots0 = ArrayList<String>()
 
     val sources: SourcesBuilder
       get() = SourcesBuilder(this)
@@ -54,9 +54,9 @@ open class ModuleBuilder(val name: String): Module {
         annotationsRoots0.add(name)
     }
 
-    public override fun getSourceFiles(): MutableList<String?>? = sourceFiles0
-    public override fun getClasspathRoots(): MutableList<String?>? = classpathRoots0
-    public override fun getAnnotationsRoots(): MutableList<String?>? = annotationsRoots0
-    public override fun getModuleName(): String? = name
+    public override fun getSourceFiles(): List<String> = sourceFiles0
+    public override fun getClasspathRoots(): List<String> = classpathRoots0
+    public override fun getAnnotationsRoots(): List<String> = annotationsRoots0
+    public override fun getModuleName(): String = name
 }
 
diff --git a/runtime/src/jet/modules/Module.java b/runtime/src/jet/modules/Module.java
index df3739fd684..07675fcc922 100644
--- a/runtime/src/jet/modules/Module.java
+++ b/runtime/src/jet/modules/Module.java
@@ -16,14 +16,23 @@
 
 package jet.modules;
 
+import jet.runtime.typeinfo.KotlinSignature;
+
 import java.util.List;
 
 /**
  * @author yole
  */
 public interface Module {
+    @KotlinSignature("fun getModuleName(): String")
     String getModuleName();
+
+    @KotlinSignature("fun getSourceFiles(): List<String>")
     List<String> getSourceFiles();
+
+    @KotlinSignature("fun getClasspathRoots(): List<String>")
     List<String> getClasspathRoots();
+
+    @KotlinSignature("fun getAnnotationsRoots(): List<String>")
     List<String> getAnnotationsRoots();
 }