jazzo

Chaps, I wonder if you can help me at all. I have a samsung spica gt i5700 and a few months ago I flashed the firmware so now I have android 2.2 on it. Yesterday I changed network provider and moved to 3 (from Tmobile) so my tmobila number will be unusable tomorrow the latest. What the idiots at tmobile failed to tell me is that the phone is locked to a t mobile simcard, so I can't use the other sim. I need to unlock the phone so I asked t mobile and they want £15 and 28 days to do it - unreasonable. Walked in the local off-license-unlocking-hut and the guy tried but it didn't manage to unlock it because he said that having flashed the operating system makes things complicated and he said he can't do it.
So now, can anybody kindly let me know how I get my phone unlocked please, any guide or anybody who can walk me through the process please?
thank you