diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnostic.java b/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnostic.java
deleted file mode 100644
index 093a90f6451..00000000000
--- a/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnostic.java
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * Copyright 2010-2012 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.jet.lang.diagnostics;
-
-import com.intellij.openapi.util.TextRange;
-import com.intellij.psi.PsiElement;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.jet.lang.psi.JetFile;
-import org.jetbrains.jet.lang.psi.JetNamedDeclaration;
-
-import java.util.List;
-
-/**
- * @author abreslav
- */
-public class RedeclarationDiagnostic extends DiagnosticWithParameters1<PsiElement, String> {
-    public RedeclarationDiagnostic(@NotNull PsiElement psiElement, @NotNull String name,
-            @NotNull RedeclarationDiagnosticFactory factory, @NotNull Severity severity) {
-        super(psiElement, name, factory, severity);
-    }
-}
diff --git a/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnosticFactory.java b/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnosticFactory.java
index bcf0598504f..023a7e8c077 100644
--- a/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnosticFactory.java
+++ b/compiler/frontend/src/org/jetbrains/jet/lang/diagnostics/RedeclarationDiagnosticFactory.java
@@ -52,8 +52,4 @@ public class RedeclarationDiagnosticFactory extends DiagnosticFactory1<PsiElemen
     public RedeclarationDiagnosticFactory(Severity severity) {
         super(severity, POSITION_REDECLARATION);
     }
-
-    public RedeclarationDiagnostic on(@NotNull PsiElement duplicatingElement, @NotNull String name) {
-        return new RedeclarationDiagnostic(duplicatingElement, name, this, severity);
-    }
 }
diff --git a/idea/src/org/jetbrains/jet/plugin/highlighter/JetPsiChecker.java b/idea/src/org/jetbrains/jet/plugin/highlighter/JetPsiChecker.java
index 96d352074f4..e024c4a2813 100644
--- a/idea/src/org/jetbrains/jet/plugin/highlighter/JetPsiChecker.java
+++ b/idea/src/org/jetbrains/jet/plugin/highlighter/JetPsiChecker.java
@@ -182,9 +182,8 @@ public class JetPsiChecker implements Annotator {
                 return;
             }
 
-            if (diagnostic instanceof RedeclarationDiagnostic) {
-                RedeclarationDiagnostic redeclarationDiagnostic = (RedeclarationDiagnostic)diagnostic;
-                registerQuickFix(markRedeclaration(redeclarations, redeclarationDiagnostic, holder), diagnostic);
+            if (diagnostic.getFactory() instanceof RedeclarationDiagnosticFactory) {
+                registerQuickFix(markRedeclaration(redeclarations, diagnostic, holder), diagnostic);
                 return;
             }
 
@@ -249,11 +248,11 @@ public class JetPsiChecker implements Annotator {
 
     @Nullable
     private static Annotation markRedeclaration(@NotNull Set<PsiElement> redeclarations,
-                                                @NotNull RedeclarationDiagnostic diagnostic,
+                                                @NotNull Diagnostic redeclarationDiagnostic,
                                                 @NotNull AnnotationHolder holder) {
-        if (!redeclarations.add(diagnostic.getPsiElement())) return null;
-        List<TextRange> textRanges = diagnostic.getTextRanges();
+        if (!redeclarations.add(redeclarationDiagnostic.getPsiElement())) return null;
+        List<TextRange> textRanges = redeclarationDiagnostic.getTextRanges();
         if (textRanges.isEmpty()) return null;
-        return holder.createErrorAnnotation(textRanges.get(0), getMessage(diagnostic));
+        return holder.createErrorAnnotation(textRanges.get(0), getMessage(redeclarationDiagnostic));
     }
 }