--- a/static/js/webrtc-adapter.js	Thu Mar 14 23:36:24 2013 +0900
+++ b/static/js/webrtc-adapter.js	Wed Nov 20 19:40:23 2013 +0900
@@ -13,7 +13,7 @@
   RTCPeerConnection = mozRTCPeerConnection;
 
   // The RTCSessionDescription object.
-  RTCSessionDescription = Object;
+  RTCSessionDescription = mozRTCSessionDescription;
 
   // The RTCIceCandidate object.
   RTCIceCandidate = mozRTCIceCandidate;