iPhone won't charge - Not charger

Hi. Today I plugged my iPhone 3G into the wall charger I have always used. It charged up to about 50% roughly then when I went and unplugged it to use it I saw a message up on the screen. I can't be sure but I think it was the "Charging is not supported with this accessory" message. Anyway now the phone won't charge at all. Either on the wall charger or the USB2 cable on my laptop. Its not either charger as I have tried my wife's iphone and it charges fine. Also when connecting to the laptop via the USB cable it doesn't come up in iTunes.

I have tried turning it off/on as well as perform a reset all settings. I haven't performed a full reset as I hadn't synced it for a while so would refer not to lose all the data.

I also tried cleaning the connectors in case it was that.

Any ideas before I have to take it back to apple?

Thanks