diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/ClassFileFactory.java b/compiler/backend/src/org/jetbrains/jet/codegen/ClassFileFactory.java
index c44321b7f46..b63d81043d4 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/ClassFileFactory.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/ClassFileFactory.java
@@ -26,6 +26,7 @@ import org.jetbrains.jet.codegen.state.GenerationStateAware;
 import org.jetbrains.jet.codegen.state.JetTypeMapperMode;
 import org.jetbrains.jet.lang.descriptors.ClassDescriptor;
 import org.jetbrains.jet.lang.psi.JetFile;
+import org.jetbrains.jet.lang.resolve.java.JvmClassName;
 import org.jetbrains.jet.lang.resolve.name.FqName;
 
 import javax.inject.Inject;
@@ -51,11 +52,14 @@ public final class ClassFileFactory extends GenerationStateAware {
         this.builderFactory = builderFactory;
     }
 
-    ClassBuilder newVisitor(String internalClassName, PsiFile sourceFile) {
-        return newVisitor(internalClassName + ".class", Collections.singletonList(sourceFile));
+    @NotNull
+    ClassBuilder newVisitor(@NotNull JvmClassName className, @NotNull PsiFile sourceFile) {
+        return newVisitor(className, Collections.singletonList(sourceFile));
     }
-    
-    private ClassBuilder newVisitor(String outputFilePath, Collection<? extends PsiFile> sourceFiles) {
+
+    @NotNull
+    private ClassBuilder newVisitor(@NotNull JvmClassName className, @NotNull Collection<? extends PsiFile> sourceFiles) {
+        String outputFilePath = className.getInternalName() + ".class";
         state.getProgress().reportOutput(toIoFilesIgnoringNonPhysical(sourceFiles), new File(outputFilePath));
         ClassBuilder answer = builderFactory.newClassBuilder();
         generators.put(outputFilePath, answer);
@@ -108,10 +112,7 @@ public final class ClassFileFactory extends GenerationStateAware {
                 @NotNull
                 @Override
                 protected ClassBuilder createClassBuilder() {
-                    return newVisitor(
-                            NamespaceCodegen.getJVMClassNameForKotlinNs(fqName).getInternalName() + ".class",
-                            files
-                    );
+                    return newVisitor(NamespaceCodegen.getJVMClassNameForKotlinNs(fqName), files);
                 }
             };
             codegen = new NamespaceCodegen(onDemand, fqName, state, files);
@@ -126,17 +127,18 @@ public final class ClassFileFactory extends GenerationStateAware {
         if (isPrimitive(type)) {
             throw new IllegalStateException("Codegen for primitive type is not possible: " + aClass);
         }
-        return newVisitor(type.getInternalName(), sourceFile);
+        return newVisitor(JvmClassName.byType(type), sourceFile);
     }
 
-    public ClassBuilder forNamespacepart(String internalName, PsiFile sourceFile) {
-        return newVisitor(internalName, sourceFile);
+    @NotNull
+    public ClassBuilder forNamespacePart(@NotNull JvmClassName name, @NotNull PsiFile sourceFile) {
+        return newVisitor(name, sourceFile);
     }
 
-    public ClassBuilder forTraitImplementation(ClassDescriptor aClass, GenerationState state, PsiFile sourceFile) {
-        return newVisitor(
-                state.getTypeMapper().mapType(aClass.getDefaultType(), JetTypeMapperMode.TRAIT_IMPL).getInternalName(),
-                sourceFile);
+    @NotNull
+    public ClassBuilder forTraitImplementation(@NotNull ClassDescriptor aClass, @NotNull GenerationState state, @NotNull PsiFile file) {
+        Type type = state.getTypeMapper().mapType(aClass.getDefaultType(), JetTypeMapperMode.TRAIT_IMPL);
+        return newVisitor(JvmClassName.byType(type), file);
     }
 
     private static Collection<File> toIoFilesIgnoringNonPhysical(Collection<? extends PsiFile> psiFiles) {
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/ClosureCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/ClosureCodegen.java
index ea860a0a78c..5c7aba35fa5 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/ClosureCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/ClosureCodegen.java
@@ -92,7 +92,7 @@ public class ClosureCodegen extends GenerationStateAware {
 
 
     public void gen() {
-        ClassBuilder cv = state.getFactory().newVisitor(name.getInternalName(), fun.getContainingFile());
+        ClassBuilder cv = state.getFactory().newVisitor(name, fun.getContainingFile());
 
         FunctionDescriptor interfaceFunction;
         String[] superInterfaces;
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
index 55aa5f13e1b..c6bdb3bc9d7 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
@@ -106,14 +106,11 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
      */
     private final Map<JetElement, StackValue.Local> tempVariables = Maps.newHashMap();
 
-    public CalculatedClosure generateObjectLiteral(
-            GenerationState state,
-            JetObjectLiteralExpression literal
-    ) {
+    public CalculatedClosure generateObjectLiteral(GenerationState state, JetObjectLiteralExpression literal) {
         JetObjectDeclaration objectDeclaration = literal.getObjectDeclaration();
 
         JvmClassName className = classNameForAnonymousClass(bindingContext, objectDeclaration);
-        ClassBuilder classBuilder = state.getFactory().newVisitor(className.getInternalName(), literal.getContainingFile());
+        ClassBuilder classBuilder = state.getFactory().newVisitor(className, literal.getContainingFile());
 
         ClassDescriptor classDescriptor = bindingContext.get(CLASS, objectDeclaration);
         assert classDescriptor != null;
@@ -286,10 +283,8 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
         ClassDescriptor descriptor = bindingContext.get(BindingContext.CLASS, declaration);
         assert descriptor != null;
 
-        JvmClassName className =
-                classNameForAnonymousClass(bindingContext, declaration);
-        ClassBuilder classBuilder = state.getFactory().newVisitor(className.getInternalName(), declaration.getContainingFile()
-        );
+        JvmClassName className = classNameForAnonymousClass(bindingContext, declaration);
+        ClassBuilder classBuilder = state.getFactory().newVisitor(className, declaration.getContainingFile());
 
         ClassContext objectContext = context.intoAnonymousClass(descriptor, this);
 
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/FunctionCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/FunctionCodegen.java
index d5aa7f2fba4..093f85a0292 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/FunctionCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/FunctionCodegen.java
@@ -321,7 +321,7 @@ public class FunctionCodegen extends GenerationStateAware {
             iv.load(k, argType);
             k += argType.getSize();
         }
-        iv.invokestatic(dk.getOwnerClass(), asmMethod.getName(), asmMethod.getDescriptor());
+        iv.invokestatic(dk.getOwnerClass().getInternalName(), asmMethod.getName(), asmMethod.getDescriptor());
         iv.areturn(asmMethod.getReturnType());
     }
 
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
index 3c5aa208d5b..4a3919d55ea 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/NamespaceCodegen.java
@@ -199,14 +199,12 @@ public class NamespaceCodegen extends MemberCodegen {
 
         if (!generateSrcClass) return null;
 
-        String namespaceInternalName = JvmClassName.byFqNameWithoutInnerClasses(
-                PackageClassUtils.getPackageClassFqName(name)).getInternalName();
-        String className = getMultiFileNamespaceInternalName(namespaceInternalName, file);
-        ClassBuilder builder = state.getFactory().forNamespacepart(className, file);
+        JvmClassName className = getMultiFileNamespaceInternalName(PackageClassUtils.getPackageClassFqName(name), file);
+        ClassBuilder builder = state.getFactory().forNamespacePart(className, file);
 
         builder.defineClass(file, V1_6,
                             ACC_PUBLIC | ACC_FINAL,
-                            className,
+                            className.getInternalName(),
                             null,
                             //"jet/lang/Namespace",
                             "java/lang/Object",
@@ -334,14 +332,19 @@ public class NamespaceCodegen extends MemberCodegen {
     }
 
     @NotNull
-    private static String getMultiFileNamespaceInternalName(@NotNull String namespaceInternalName, @NotNull PsiFile file) {
+    private static JvmClassName getMultiFileNamespaceInternalName(@NotNull FqName facadeFqName, @NotNull PsiFile file) {
         String fileName = FileUtil.getNameWithoutExtension(PathUtil.getFileName(file.getName()));
 
         // path hashCode to prevent same name / different path collision
-        return namespaceInternalName + "$src$" + replaceSpecialSymbols(fileName) + "$" + Integer.toHexString(
+        String srcName = facadeFqName.shortName().asString() + "$src$" + replaceSpecialSymbols(fileName) + "$" + Integer.toHexString(
                 CodegenUtil.getPathHashCode(file));
+
+        FqName srcFqName = facadeFqName.parent().child(Name.identifier(srcName));
+
+        return JvmClassName.byFqNameWithoutInnerClasses(srcFqName);
     }
 
+    @NotNull
     private static String replaceSpecialSymbols(@NotNull String str) {
         return str.replace('.', '_');
     }
@@ -349,8 +352,7 @@ public class NamespaceCodegen extends MemberCodegen {
     @NotNull
     public static String getNamespacePartInternalName(@NotNull JetFile file) {
         FqName fqName = JetPsiUtil.getFQName(file);
-        JvmClassName namespaceJvmClassName = NamespaceCodegen.getJVMClassNameForKotlinNs(fqName);
-        String namespaceInternalName = namespaceJvmClassName.getInternalName();
-        return NamespaceCodegen.getMultiFileNamespaceInternalName(namespaceInternalName, file);
+        JvmClassName namespaceJvmClassName = getJVMClassNameForKotlinNs(fqName);
+        return getMultiFileNamespaceInternalName(namespaceJvmClassName.getFqName(), file).getInternalName();
     }
 }
\ No newline at end of file
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/OwnerKind.java b/compiler/backend/src/org/jetbrains/jet/codegen/OwnerKind.java
index 2856263c632..67c2f8d5fd6 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/OwnerKind.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/OwnerKind.java
@@ -16,10 +16,13 @@
 
 package org.jetbrains.jet.codegen;
 
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.jet.lang.resolve.java.JvmClassName;
+
 public class OwnerKind {
     private final String name;
 
-    protected OwnerKind(String name) {
+    protected OwnerKind(@NotNull String name) {
         this.name = name;
     }
 
@@ -28,14 +31,15 @@ public class OwnerKind {
     public static final OwnerKind TRAIT_IMPL = new OwnerKind("trait implementation");
 
     public static class StaticDelegateKind extends OwnerKind {
-        private final String ownerClass;
+        private final JvmClassName ownerClass;
 
-        public StaticDelegateKind(String ownerClass) {
+        public StaticDelegateKind(@NotNull JvmClassName ownerClass) {
             super("staticDelegateKind");
             this.ownerClass = ownerClass;
         }
 
-        public String getOwnerClass() {
+        @NotNull
+        public JvmClassName getOwnerClass() {
             return ownerClass;
         }
     }
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/SamWrapperCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/SamWrapperCodegen.java
index 1e90036254c..2878677057b 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/SamWrapperCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/SamWrapperCodegen.java
@@ -63,7 +63,7 @@ public class SamWrapperCodegen extends GenerationStateAware {
         // e.g. compare(T, T)
         SimpleFunctionDescriptor interfaceFunction = SingleAbstractMethodUtils.getAbstractMethodOfSamInterface(samInterface);
 
-        ClassBuilder cv = state.getFactory().newVisitor(name.getInternalName(), file);
+        ClassBuilder cv = state.getFactory().newVisitor(name, file);
         cv.defineClass(file,
                        V1_6,
                        ACC_FINAL,
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/ScriptCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/ScriptCodegen.java
index 8d18cb286b1..b1aa0a99926 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/ScriptCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/ScriptCodegen.java
@@ -77,8 +77,7 @@ public class ScriptCodegen extends MemberCodegen {
         JvmClassName className = bindingContext.get(FQN, classDescriptorForScript);
         assert className != null;
 
-        ClassBuilder classBuilder = classFileFactory.newVisitor(className.getInternalName(), scriptDeclaration.getContainingFile()
-        );
+        ClassBuilder classBuilder = classFileFactory.newVisitor(className, scriptDeclaration.getContainingFile());
         classBuilder.defineClass(scriptDeclaration,
                                  V1_6,
                                  ACC_PUBLIC,
diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java b/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java
index aaef6ff3338..f66010be3f8 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/context/CodegenContext.java
@@ -29,6 +29,7 @@ import org.jetbrains.jet.lang.descriptors.annotations.AnnotationDescriptor;
 import org.jetbrains.jet.lang.descriptors.impl.ConstructorDescriptorImpl;
 import org.jetbrains.jet.lang.resolve.BindingContext;
 import org.jetbrains.jet.lang.resolve.DescriptorUtils;
+import org.jetbrains.jet.lang.resolve.java.JvmClassName;
 
 import java.util.Collections;
 import java.util.HashMap;
@@ -152,7 +153,7 @@ public abstract class CodegenContext<T extends DeclarationDescriptor> {
     }
 
     @NotNull
-    public FieldOwnerContext intoNamespacePart(String delegateTo, NamespaceDescriptor descriptor) {
+    public FieldOwnerContext intoNamespacePart(@NotNull JvmClassName delegateTo, @NotNull NamespaceDescriptor descriptor) {
         return new NamespaceContext(descriptor, this, new OwnerKind.StaticDelegateKind(delegateTo));
     }