diff --git a/content/media/ogg/nsOggDecoder.h b/content/media/ogg/nsOggDecoder.h
index afe3d4e6a4a..84310670e1a 100644
--- a/content/media/ogg/nsOggDecoder.h
+++ b/content/media/ogg/nsOggDecoder.h
@@ -44,7 +44,12 @@
 class nsOggDecoder : public nsBuiltinDecoder
 {
 public:
-  virtual nsMediaDecoder* Clone() { return new nsOggDecoder(); }
+  virtual nsMediaDecoder* Clone() {
+    if (!nsHTMLMediaElement::IsOggEnabled()) {
+      return nsnull;
+    }
+    return new nsOggDecoder();
+  }
   virtual nsDecoderStateMachine* CreateStateMachine();
 };
 
diff --git a/content/media/raw/nsRawDecoder.h b/content/media/raw/nsRawDecoder.h
index 029253e897a..fd21a3c8239 100644
--- a/content/media/raw/nsRawDecoder.h
+++ b/content/media/raw/nsRawDecoder.h
@@ -42,7 +42,12 @@
 class nsRawDecoder : public nsBuiltinDecoder
 {
 public:
-  virtual nsMediaDecoder* Clone() { return new nsRawDecoder(); }
+  virtual nsMediaDecoder* Clone() { 
+    if (!nsHTMLMediaElement::IsRawEnabled()) {
+      return nsnull;
+    }    
+    return new nsRawDecoder();
+  }
   virtual nsDecoderStateMachine* CreateStateMachine();
 };
 
diff --git a/content/media/wave/nsWaveDecoder.h b/content/media/wave/nsWaveDecoder.h
index 220a6ef21fe..8fbb6bb9e98 100644
--- a/content/media/wave/nsWaveDecoder.h
+++ b/content/media/wave/nsWaveDecoder.h
@@ -55,8 +55,13 @@
 class nsWaveDecoder : public nsBuiltinDecoder
 {
 public:
-   virtual nsMediaDecoder* Clone() { return new nsWaveDecoder(); }
-   virtual nsDecoderStateMachine* CreateStateMachine();
+  virtual nsMediaDecoder* Clone() {
+    if (!nsHTMLMediaElement::IsWaveEnabled()) {
+      return nsnull;
+    }
+    return new nsWaveDecoder();
+  }
+  virtual nsDecoderStateMachine* CreateStateMachine();
 };
 
 #endif
diff --git a/content/media/webm/nsWebMDecoder.h b/content/media/webm/nsWebMDecoder.h
index ab003dcb73f..a7fb6584636 100644
--- a/content/media/webm/nsWebMDecoder.h
+++ b/content/media/webm/nsWebMDecoder.h
@@ -44,7 +44,12 @@
 class nsWebMDecoder : public nsBuiltinDecoder
 {
 public:
-  virtual nsMediaDecoder* Clone() { return new nsWebMDecoder(); }
+  virtual nsMediaDecoder* Clone() {
+    if (!nsHTMLMediaElement::IsWebMEnabled()) {
+      return nsnull;
+    }
+    return new nsWebMDecoder();
+  }
   virtual nsDecoderStateMachine* CreateStateMachine();
 };