I posted this a few days ago with only one reply back. I recently upgraded my iphone 3g to 3.0 followed by a jailbreak. Everything is fine but i recently tried to back up my iphone because i added several new contacts. Itunes comes back with an error saying the (Itunes can not back up Iphone has disconnected). I have tried restarting my mac, rebooting my Iphone. Any help would be great. 
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