Question : unlock jailbroken iphone 3GS 3.1.3 model 5.12.01

I hope someone can help me please.  I would like to go to TMobile.  My phone is jailbroken with Spirit, serial number is 38.  Is it possible to unlock?  I am hesitant do anything until I know for sure, I think I made a mistake by using Spirit.  Phone is new to me, so no history.   I found this with Pawnage, but not sure if it will work for me.  
http://thebigboss.org/guides/pwnage-20-guide

Vers, 3.1.3 (7E18)
serial: 85938.........
Model MB717LL
Firmware 05.12.01
Itunes 9.1.1 (12)

I have a T-Mobile Sim Card
And the old AT&T sim

I tried spirit, Cydia installed.

Thank you.

Answer : unlock jailbroken iphone 3GS 3.1.3 model 5.12.01

It's not correct.
Few days ago I heard 4 unlocked phones, 3G and 3GS with this 3.1.3 and 05.12.01. I will know for sure this weekend. I do not think that I can post here such links, so use Google. I do not remember if it was about Ultrasn0w or Blacksn0w, but I heard that only one works.