Issue with _changedoc function

When you receive a 'changed' event, get an error stating,
Uncaught TypeError: Cannot read property 'id' of undefined
at MeteorDdp._changeDoc (meteor-ddp.js:114)
at WebSocket.self.sock.onmessage (meteor-ddp.js:55)
MeteorDdp._changeDoc @ meteor-ddp.js:114
self.sock.onmessage @ meteor-ddp.js:55

This error comes on subscription.

nevermind I solved the issue by commenting
coll = this.collections[collName]; and declaring
var coll = {};
coll[id] = {};

But now there's one small problem, subscription isn't working, ie. I don't get notified on the arrival of any subscribed messages.