Is pub/sub from trunk broken?

[Han Nguyen]

Hello,
My teammate and I synched down the code from the trunk yesterday, and our 
previously working pub/sub test cases are now broken with the below error 
found in FF console.
Has anyone seen this error? is pub/sub broken?

uncaught exception: An invalid or illegal string was specified 
(NS_ERROR_DOM_SYNTAX_ERR)
        targetWin.postMessage(gadgets.json.stringify(rpc), relay);

Thanks much!
Han