Don't try cutting your Virgin sim up - my bil tried it before he contacted them, and it wouldn't work - just kept saying there was no sim installed. He had to then pretend he'd accidentally damaged it to get a new one. I wonder if it depends which tarrif you're on. They definitely told him they couldn't support the iphone though because he did it through that 'chat to a representative' instant messaging they have and I saw the answer come up on the screen. He's changed to t-mobile now through and they've given him 1 year free internet, so he's happy enough.