Yes, Anwarpp is 100% true and correct... Please read carefully so nobody get confuse at the end:

Having version5.11 of modem firmware is impossible to unlock for the momment. It will take long, long, long time before software will come to unlock this baseband.

For Camelme>>

if your iphone is jailbroken and unlocked with 3.1.2, then you must check 4 things:

1. Check if you have Cydia or Icy
2. Check if which baseband you currently use
3. Check if you had turbo sim

If you can place a call (incoming and outgoing call)and your 3G or 3GS have Cydia or Icy and the baseband or modemfrimware id 5.11.07, then you may contact me or just PM me so I can give you a bunch of my customer who needs your help. Doesn't matter if it is 3.1 or 3.1.2 or even 3.0.1 or 3.0. People needs that it will work (means unlock).

However, If you are trying to say that it works from you but you cant tell if which baseband you are currently use, then check the 4 and foremost:

4. Check if which Generation your iPhone. Is it 3G or 3GS? If so, then just PM me and I will give you the customers like what I said. BUT......
If your iPhone is just 2G, then YES, you can do jailbreak/unlock it again. The reason is very simple: "Your baseband or modem version are still and it will remain 04.05.04

For Those who read this blog: PM me if you find difficulties for the above subject!!!