Help unlock 3GS

[brokencoffee]

this is a fun one..
someone gave me a 3GS because they did ''something to it'' (trying tjailbreak)
the person has no brains to tell me what program they used, (some online youtube vid )
all i know is they THINK its 4 OS. '
itsasking me to download 5.0.1 from itunes which im NOT going to do.
i think its 4.0 software..
someone help me jailbreak and unlock to use on Tnmobile network>? dont care what OS i run.
would prefer4.0 8l1or 2?want untethered.

gaa this is a mess.

 

[sbddude]

Need to figure out which version it's Currently on beefier anyone can help...

Settings, general, about

 

[brokencoffee]

nada.. stuck on ''connect to itunes'' screen. lets just imagine its the Stock IOS that comes with brand new Iphone 3GS. i seriosly dought it was updated.

 

[brokencoffee]

Fixed..now to unlock?

with Tiny umbrella, and Recboot on itumes 9.1 i installed OS 4.0 (8A293) on Baseband 06.15.00
jailbroken with Limera1n. now.. how do i go about unlocking for use with Tmobile Sim?
or is this a noncompaable OS for unlock? Cydia is NOT installed, going to SSH install the DEB.