Google Channel API - Socket not opening on some clients

I've been developing a simple chat application using the XMPP Service and the Channel service. I've been able to get it functioning correctly at home. However, when another user tries to access the site, the onOpen callback method is not being called. I've tried it from various locations using FireFox 3.6+ and Chrome and it has worked for me(at home, at work).

Is it possible that this is being blocked by a system administrator if the user is accessing it from a work location? Or could it be the browser being used? I had this person try with FireFox and Chrome. I wasn't there so I'm not certain which browser version wa开发者_如何学运维s used. IE hasn't worked for me so I'm not concerned with that one.

Any insight is greatly appreciated.

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Hmm. Since the Channel API uses Google Talk infrastructure, and an iframe pointed at the Google Talk frontends, the Channel API could be blocked by an administrator even if the main app isn't blocked. Specifically if a proxy is blocking talkgadget.google.com, the Channel API will fail to load.

I created a feature request for this here: http://code.google.com/p/googleappengine/issues/detail?id=4764, feel free to vote it up.