Thanks, it's not a matter of saving a few quid, it just makes it easier to put one of our t-mobile business sims and keep all our phone costs to one bill.
I found this site which looks like it could do the trick....
http://www.unlockiphonehq.com/
I am a bit wary so if anyone has more info I'm listening. Thanks
Mark.
I'd be very wary - most of these sites usually have some repackaged form of the free tool which the original creators made.
I also believe that you can use a turboSIM with a 3G to get it unlocked, but not 100% on that one.