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gmail/google doesn't support safari for chat yet. other than to use a different browser that does support it, there is absolutely nothing you can do to get it to work.
 
There's nothing you can do for now. Hopefully (maybe with Safari for windows now) this will be remedied soon.

But if you're using a mac you can set up iChat to work with your gmail contact list. Only negative I see is the monkey smiley doesn't work.
 
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