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I dont have and iPhone yet, but will also be using Rogers.

I have read that you can just go into EDGE in the connection settings and with an unlocked phone you can mess with the settings and just set then to something invalid. If there is a URL instead of it having a .com address just change it to something random.

In v.1.1.1 there will be the option to switch the EDGE on and off, but v.1.1.1 might also lock your unlocked iPhone.
 
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