diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetMultiDeclarationEntry.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetMultiDeclarationEntry.java
index 9e4f01ac9dd..d9619839c50 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetMultiDeclarationEntry.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetMultiDeclarationEntry.java
@@ -38,6 +38,7 @@ public class JetMultiDeclarationEntry extends JetNamedDeclarationNotStubbed impl
         return TypeRefHelpersPackage.getTypeRef(this);
     }
 
+    @Override
     @Nullable
     public JetTypeReference setTypeRef(@Nullable JetTypeReference typeRef) {
         return TypeRefHelpersPackage.setTypeRef(this, getNameIdentifier(), typeRef);
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetProperty.java b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetProperty.java
index 30bc9b0733b..c1fd473753a 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetProperty.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/psi/JetProperty.java
@@ -149,6 +149,7 @@ public class JetProperty extends JetTypeParameterListOwnerStub<PsiJetPropertyStu
         return TypeRefHelpersPackage.getTypeRef(this);
     }
 
+    @Override
     @Nullable
     public JetTypeReference setTypeRef(@Nullable JetTypeReference typeRef) {
         return TypeRefHelpersPackage.setTypeRef(this, getNameIdentifier(), typeRef);
diff --git a/idea/src/org/jetbrains/jet/plugin/actions/JetChangeFunctionSignatureAction.java b/idea/src/org/jetbrains/jet/plugin/actions/JetChangeFunctionSignatureAction.java
index c17f8afec08..d51821c955e 100644
--- a/idea/src/org/jetbrains/jet/plugin/actions/JetChangeFunctionSignatureAction.java
+++ b/idea/src/org/jetbrains/jet/plugin/actions/JetChangeFunctionSignatureAction.java
@@ -29,6 +29,7 @@ import com.intellij.util.PlatformIcons;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.lang.descriptors.FunctionDescriptor;
 import org.jetbrains.jet.lang.psi.JetNamedFunction;
+import org.jetbrains.jet.lang.psi.JetParameterList;
 import org.jetbrains.jet.lang.psi.JetPsiFactory;
 import org.jetbrains.jet.lang.psi.JetTypeReference;
 import org.jetbrains.jet.plugin.JetBundle;
@@ -143,8 +144,8 @@ public class JetChangeFunctionSignatureAction implements QuestionAction {
                             ShortenReferences.INSTANCE$.process(newTypeRef);
                         }
 
-                        function.getValueParameterList().replace(patternFunction.getValueParameterList());
-                        ShortenReferences.INSTANCE$.process(function.getValueParameterList());
+                        JetParameterList newParameterList = (JetParameterList) function.getValueParameterList().replace(patternFunction.getValueParameterList());
+                        ShortenReferences.INSTANCE$.process(newParameterList);
                     }
                 });
             }