What I meant was.....that if you unlock a Tmobile phone and stick say an Orange sim in it, the WAP wont work without setting up usually via orange via a sim update or something.

If its on Tmobile its generally locked to that network, although you can use Virgin sims in them as well as they share the same network (its Tmobiles though). Unlocking can be done at a cost of usually 5-10 quid at most phone specialists (think market stalls over places like the Link).

Orange lock their phones too, most o2 and Voda ones are not. The only issue is if you do get it unlocked, the voicemail and wap and sometimes messsage centre numbers need to be set up, not that difficult but if you sell it to someone and they have trouble they might moan.

Sell it on ebay, lots of people sell Tmobile phone, just put easy to unlock in the description.

am getting a new phone soon and may as well sell old one.........

its a T610,

but i got it with a contract on t-mobile, does this mean i can only sell it to someone with a t-mobile sim?

would i need to wipe anything off it or is everything on my sim???