First i want to thank GEOHOT for the Unlock! He's the iPhone Hacker GOD!

But my question is it possible to use the Dev Team's 1.1.3 update/ jailbreak on my new babie?

Unlock Solution for 1.1.2 OTB Jailbroke:

Yes! I am 100% sure about this since I've got a fully functional, soft-unlocked 1.1.2 OTB lying in front of me. Here is a short and simple tutorial:

1. Open Instller on your jailbroken 1.1.2 OTB and install OpenSSH and Term-vt100 (under System)
2. Connect via WiFi to your iPhone using WinSCP
3. Copy all the files (gunlock, ICE04.02.13_G.fls and secpac) to /usr/bin
4. Set permissions of gunlock to 755 in WinSCP
5. Put iPhone in Airplane mode (IMPORTANT!)
6. Execute the following commands in Terminal:

launchctl unload -w /System/Library/LaunchDaemons/

./gunlock secpack ICE04.02.13_G.fls

launchctl load -w /System/Library/LaunchDaemons/

7. Restart iPhone and throw your ***sim out of the window