diff --git a/js/js.tests/test/org/jetbrains/k2js/test/semantics/MiscTest.java b/js/js.tests/test/org/jetbrains/k2js/test/semantics/MiscTest.java
index feaffab05bf..04c8335fc9f 100644
--- a/js/js.tests/test/org/jetbrains/k2js/test/semantics/MiscTest.java
+++ b/js/js.tests/test/org/jetbrains/k2js/test/semantics/MiscTest.java
@@ -25,8 +25,7 @@ import static org.jetbrains.k2js.test.utils.JsTestUtils.failsOnEcmaV5;
 /**
  * @author Pavel Talanov
  *         <p/>
- *         This class contains tests that do not fall in any particular category
- *         most probably because that functionality has very little support
+ *         A messy class where all new tests go before they are sorted which never happens.
  */
 public final class MiscTest extends AbstractExpressionTest {
 
@@ -148,4 +147,12 @@ public final class MiscTest extends AbstractExpressionTest {
     }
 
 
+    public void testExclExclThrows() throws Exception {
+        try {
+            fooBoxTest();
+            fail();
+        }
+        catch (JavaScriptException e) {
+        }
+    }
 }
diff --git a/js/js.translator/src/org/jetbrains/k2js/translate/context/Namer.java b/js/js.translator/src/org/jetbrains/k2js/translate/context/Namer.java
index dc8c52adffe..3d792f17527 100644
--- a/js/js.translator/src/org/jetbrains/k2js/translate/context/Namer.java
+++ b/js/js.translator/src/org/jetbrains/k2js/translate/context/Namer.java
@@ -16,9 +16,7 @@
 
 package org.jetbrains.k2js.translate.context;
 
-import com.google.dart.compiler.backend.js.ast.JsName;
-import com.google.dart.compiler.backend.js.ast.JsNameRef;
-import com.google.dart.compiler.backend.js.ast.JsScope;
+import com.google.dart.compiler.backend.js.ast.*;
 import com.google.dart.compiler.util.AstUtil;
 import org.jetbrains.annotations.NotNull;
 
@@ -44,6 +42,7 @@ public final class Namer {
     private static final String ROOT_NAMESPACE = "Root";
     private static final String RECEIVER_PARAMETER_NAME = "receiver";
     private static final String CLASSES_OBJECT_NAME = "classes";
+    private static final String THROW_NPE_FUN_NAME = "throwNPE";
 
     @NotNull
     public static String getReceiverParameterName() {
@@ -123,25 +122,32 @@ public final class Namer {
     }
 
     @NotNull
-    public JsNameRef classCreationMethodReference() {
+    public JsExpression classCreationMethodReference() {
         return kotlin(createMethodReference(className));
     }
 
     @NotNull
-    public JsNameRef traitCreationMethodReference() {
+    public JsExpression traitCreationMethodReference() {
         return kotlin(createMethodReference(traitName));
     }
 
     @NotNull
-    public JsNameRef namespaceCreationMethodReference() {
+    public JsExpression namespaceCreationMethodReference() {
         return kotlin(createMethodReference(namespaceName));
     }
 
     @NotNull
-    public JsNameRef objectCreationMethodReference() {
+    public JsExpression objectCreationMethodReference() {
         return kotlin(createMethodReference(objectName));
     }
 
+    @NotNull
+    public JsExpression throwNPEFunctionCall() {
+        JsNameRef reference = AstUtil.newQualifiedNameRef(THROW_NPE_FUN_NAME);
+        JsInvocation invocation = AstUtil.newInvocation(reference);
+        return kotlin(invocation);
+    }
+
     @NotNull
     private static JsNameRef createMethodReference(@NotNull JsName name) {
         JsNameRef qualifier = name.makeRef();
@@ -151,7 +157,7 @@ public final class Namer {
     }
 
     @NotNull
-    private JsNameRef kotlin(@NotNull JsNameRef reference) {
+    private JsExpression kotlin(@NotNull JsExpression reference) {
         JsNameRef kotlinReference = kotlinName.makeRef();
         setQualifier(reference, kotlinReference);
         return reference;
@@ -163,7 +169,7 @@ public final class Namer {
     }
 
     @NotNull
-    public JsNameRef isOperationReference() {
+    public JsExpression isOperationReference() {
         return kotlin(AstUtil.newQualifiedNameRef("isType"));
     }
 
diff --git a/js/js.translator/src/org/jetbrains/k2js/translate/operation/UnaryOperationTranslator.java b/js/js.translator/src/org/jetbrains/k2js/translate/operation/UnaryOperationTranslator.java
index dee9b1b2b32..8d5bba28ff9 100644
--- a/js/js.translator/src/org/jetbrains/k2js/translate/operation/UnaryOperationTranslator.java
+++ b/js/js.translator/src/org/jetbrains/k2js/translate/operation/UnaryOperationTranslator.java
@@ -64,7 +64,7 @@ public final class UnaryOperationTranslator {
     private static JsExpression translateExclExclOperator(@NotNull JetUnaryExpression expression, @NotNull TranslationContext context) {
         JsExpression translatedExpression = translateAsExpression(getBaseExpression(expression), context);
         JsBinaryOperation notNullCheck = notNullCheck(context, translatedExpression);
-        return new JsConditional(notNullCheck, translatedExpression, translatedExpression);
+        return new JsConditional(notNullCheck, translatedExpression, context.namer().throwNPEFunctionCall());
     }
 
     @NotNull
diff --git a/js/js.translator/testFiles/kotlin_lib.js b/js/js.translator/testFiles/kotlin_lib.js
index af8de4b708f..8453ae4410c 100644
--- a/js/js.translator/testFiles/kotlin_lib.js
+++ b/js/js.translator/testFiles/kotlin_lib.js
@@ -286,7 +286,12 @@ var Kotlin;
 
     Kotlin.Exceptions = {};
     Kotlin.Exception = Kotlin.Class.create();
-    Kotlin.Exceptions.IndexOutOfBounds = {};
+    Kotlin.Exceptions.IndexOutOfBounds = Kotlin.Class.create(Kotlin.Exception);
+    Kotlin.Exceptions.NullPointerException = Kotlin.Class.create(Kotlin.Exception);
+
+    Kotlin.throwNPE = function() {
+        throw new Kotlin.Exceptions.NullPointerException();
+    };
 
 
     Kotlin.ArrayList = Class.create({