Sim cards for orange PAYG

[chopper1]

Hi Guys,
i have a couple of spare orange pay as you go sim cards with about £20 credit on them, i want to keep my present phone number and sim card, how can i add the credit of the spare sim cards on to my present sim card, is there a simple way of doing this, or will i have to use each sim card seperately and register with orange for a new phone number?. Help much appreciated.
thanks, Chopper.

[Prontopro]

I would have thought that if the cards are registered in your name then you'd simply call Orange and ask them to transfer the credit to the new number.

If they can't then they'll explain why.