diff --git a/platform/platform-impl/src/com/intellij/openapi/vfs/encoding/EncodingProjectManagerImpl.java b/platform/platform-impl/src/com/intellij/openapi/vfs/encoding/EncodingProjectManagerImpl.java
index 495d72e63178..826028cdd21b 100644
--- a/platform/platform-impl/src/com/intellij/openapi/vfs/encoding/EncodingProjectManagerImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/vfs/encoding/EncodingProjectManagerImpl.java
@@ -210,17 +210,22 @@ public class EncodingProjectManagerImpl extends EncodingProjectManager {
 
   @Override
   public void setEncoding(@Nullable final VirtualFile virtualFileOrDir, @Nullable final Charset charset) {
+    Charset oldCharset;
+
     if (charset == null) {
-      myMapping.remove(virtualFileOrDir);
+      oldCharset = myMapping.remove(virtualFileOrDir);
     }
     else {
-      myMapping.put(virtualFileOrDir, charset);
+      oldCharset = myMapping.put(virtualFileOrDir, charset);
     }
-    myModificationCount++;
-    if (virtualFileOrDir != null) {
-      virtualFileOrDir.setCharset(virtualFileOrDir.getBOM() == null ? charset : null);
+
+    if (!Comparing.equal(oldCharset, charset)) {
+      myModificationCount++;
+      if (virtualFileOrDir != null) {
+        virtualFileOrDir.setCharset(virtualFileOrDir.getBOM() == null ? charset : null);
+      }
+      reloadAllFilesUnder(virtualFileOrDir);
     }
-    reloadAllFilesUnder(virtualFileOrDir);
   }
 
   private static void clearAndReload(@NotNull VirtualFile virtualFileOrDir) {
diff --git a/platform/util/src/com/intellij/util/ArrayUtil.java b/platform/util/src/com/intellij/util/ArrayUtil.java
index 3f1470ad9a56..40e3f84ede22 100644
--- a/platform/util/src/com/intellij/util/ArrayUtil.java
+++ b/platform/util/src/com/intellij/util/ArrayUtil.java
@@ -685,6 +685,21 @@ public class ArrayUtil extends ArrayUtilRt {
     return indexOf(objects, o) >= 0;
   }
 
+  public static boolean contains(@Nullable final String s, final String... strings) {
+    if (s == null) {
+      for (String str : strings) {
+        if (str == null) return true;
+      }
+    }
+    else {
+      for (String str : strings) {
+        if (s.equals(str)) return true;
+      }
+    }
+
+    return false;
+  }
+
   @NotNull
   public static int[] newIntArray(int count) {
     return count == 0 ? EMPTY_INT_ARRAY : new int[count];