diff --git a/widget/src/cocoa/nsSound.h b/widget/src/cocoa/nsSound.h
index e0711b2e29fb..94a166b9ab20 100644
--- a/widget/src/cocoa/nsSound.h
+++ b/widget/src/cocoa/nsSound.h
@@ -21,6 +21,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Stuart Parmenter <stuart@mozilla.com>
  *   Vladimir Vukicevic <vladimir@pobox.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
@@ -48,12 +49,12 @@ class nsSound : public nsISound,
 
 {
 public: 
-  nsSound();
-  virtual ~nsSound();
+    nsSound();
+    virtual ~nsSound();
 
-  NS_DECL_ISUPPORTS
-  NS_DECL_NSISOUND
-  NS_DECL_NSISTREAMLOADEROBSERVER
+    NS_DECL_ISUPPORTS
+    NS_DECL_NSISOUND
+    NS_DECL_NSISTREAMLOADEROBSERVER
 };
 
 #endif
diff --git a/widget/src/cocoa/nsSound.mm b/widget/src/cocoa/nsSound.mm
index 6a7fc2714524..40cc7694a42d 100644
--- a/widget/src/cocoa/nsSound.mm
+++ b/widget/src/cocoa/nsSound.mm
@@ -21,6 +21,7 @@
  * the Initial Developer. All Rights Reserved.
  *
  * Contributor(s):
+ *   Stuart Parmenter <stuart@mozilla.com>
  *   Vladimir Vukicevic <vladimir@pobox.com>
  *
  * Alternatively, the contents of this file may be used under the terms of
@@ -39,6 +40,13 @@
 
 #include "nsSound.h"
 
+#include <Foundation/NSData.h>
+#include <AppKit/NSSound.h>
+
+#include "nsNetUtil.h"
+#include "nsCOMPtr.h"
+#include "nsIURL.h"
+
 NS_IMPL_ISUPPORTS1(nsSound, nsISound)
 
 nsSound::nsSound()
@@ -62,13 +70,23 @@ nsSound::OnStreamComplete(nsIStreamLoader *aLoader,
                           PRUint32 dataLen,
                           const PRUint8 *data)
 {
+    NSData *value = [NSData dataWithBytes:data length:dataLen];
+
+    NSSound *sound = [[NSSound alloc] initWithData:value];
+
+    [sound play];
+
+    [sound autorelease];
+
     return NS_OK;
 }
 
 NS_IMETHODIMP
 nsSound::Play(nsIURL *aURL)
 {
-    return NS_OK;
+    nsCOMPtr<nsIURI> uri(do_QueryInterface(aURL));
+    nsCOMPtr<nsIStreamLoader> loader;
+    return NS_NewStreamLoader(getter_AddRefs(loader), uri, this);
 }
 
 NS_IMETHODIMP