problem recharging phone

[Guest pk_volt]

When I plug the wall charger into the phone, all is great, the red led light on the top right corner comes on, and you can see the wall charger symbol on the lcd screen.

But after like 5 minutes, you can hear the disconnect tone on the phone, an amber light blinks a few times, and the led turns off, and the disconnect tone goes on, signalling that the wall charger has disconnected.

Anyone here had this problem before?