diff --git a/java/java-impl/src/com/intellij/psi/impl/PsiClassImplUtil.java b/java/java-impl/src/com/intellij/psi/impl/PsiClassImplUtil.java
index 5a0878ca003d..14c300586ff6 100644
--- a/java/java-impl/src/com/intellij/psi/impl/PsiClassImplUtil.java
+++ b/java/java-impl/src/com/intellij/psi/impl/PsiClassImplUtil.java
@@ -838,13 +838,22 @@ public class PsiClassImplUtil {
       return true;
     }
 
-    final ProjectFileIndex fileIndex = ProjectRootManager.getInstance(aClass.getProject()).getFileIndex();
     final PsiFile file1 = aClass.getContainingFile().getOriginalFile();
     final PsiFile file2 = another.getContainingFile().getOriginalFile();
     if (file1.equals(file2)) {
       return true;
     }
 
+    //see com.intellij.openapi.vcs.changes.PsiChangeTracker
+    //see com.intellij.psi.impl.PsiFileFactoryImpl#createFileFromText(CharSequence,PsiFile)
+    final PsiFile original1 = file1.getUserData(PsiFileFactory.ORIGINAL_FILE);
+    final PsiFile original2 = file2.getUserData(PsiFileFactory.ORIGINAL_FILE);
+    if ((original1 == original2 && original1 != null)
+        || original1 == file2 || original2 == file1) {
+      return true;
+    }    
+
+    final ProjectFileIndex fileIndex = ProjectRootManager.getInstance(aClass.getProject()).getFileIndex();
     final VirtualFile vfile1 = file1.getViewProvider().getVirtualFile();
     final VirtualFile vfile2 = file2.getViewProvider().getVirtualFile();
     if ((fileIndex.isInSource(vfile1) || fileIndex.isInLibraryClasses(vfile1)) &&
diff --git a/platform/lang-api/src/com/intellij/psi/PsiFileFactory.java b/platform/lang-api/src/com/intellij/psi/PsiFileFactory.java
index 06a42cc92bf6..63e8be5c4251 100644
--- a/platform/lang-api/src/com/intellij/psi/PsiFileFactory.java
+++ b/platform/lang-api/src/com/intellij/psi/PsiFileFactory.java
@@ -7,10 +7,13 @@ import com.intellij.lang.Language;
 import com.intellij.openapi.components.ServiceManager;
 import com.intellij.openapi.fileTypes.FileType;
 import com.intellij.openapi.project.Project;
+import com.intellij.openapi.util.Key;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 public abstract class PsiFileFactory {
+  public static Key<PsiFile> ORIGINAL_FILE = Key.create("ORIGINAL_FILE");
   public static PsiFileFactory getInstance(Project project) {
     return ServiceManager.getService(project, PsiFileFactory.class);
   }
@@ -43,4 +46,7 @@ public abstract class PsiFileFactory {
                                              boolean physical, boolean markAsCopy);
 
   public abstract PsiFile createFileFromText(FileType fileType, String fileName, CharSequence chars, int startOffset, int endOffset);
+
+  @Nullable
+  public abstract PsiFile createFileFromText(@NotNull CharSequence chars, @NotNull PsiFile original);  
 }
\ No newline at end of file
diff --git a/platform/lang-impl/src/com/intellij/openapi/vcs/changes/PsiChangeTracker.java b/platform/lang-impl/src/com/intellij/openapi/vcs/changes/PsiChangeTracker.java
index 9679c61814e0..7613f3239473 100644
--- a/platform/lang-impl/src/com/intellij/openapi/vcs/changes/PsiChangeTracker.java
+++ b/platform/lang-impl/src/com/intellij/openapi/vcs/changes/PsiChangeTracker.java
@@ -39,9 +39,7 @@ public class PsiChangeTracker {
     final List<T> elements = new ArrayList<T>();
     final List<T> oldElements = new ArrayList<T>();
     final PsiFile oldFile = oldText == null
-                            ? null
-                            : PsiFileFactory.getInstance(project)
-                              .createFileFromText(file.getName(), file.getLanguage(), oldText, false, true);
+                            ? null : PsiFileFactory.getInstance(project).createFileFromText(oldText, file);
 
     file.accept(new MyVisitor<T>(filter, elements));
 
diff --git a/platform/lang-impl/src/com/intellij/psi/impl/PsiFileFactoryImpl.java b/platform/lang-impl/src/com/intellij/psi/impl/PsiFileFactoryImpl.java
index 5ff90fe67b55..62b481a28b1d 100644
--- a/platform/lang-impl/src/com/intellij/psi/impl/PsiFileFactoryImpl.java
+++ b/platform/lang-impl/src/com/intellij/psi/impl/PsiFileFactoryImpl.java
@@ -141,4 +141,13 @@ public class PsiFileFactoryImpl extends PsiFileFactory {
     return createFileFromText(fileName, fileType, text);
   }
 
+  @Nullable
+  @Override
+  public PsiFile createFileFromText(@NotNull CharSequence chars, @NotNull PsiFile original) {
+    final PsiFile file = createFileFromText(original.getName(), original.getLanguage(), chars, false, true);
+    if (file != null) {
+      file.putUserData(ORIGINAL_FILE, original);
+    }
+    return file;
+  }
 }