For those iphones who have problem after jailbreak and unlock need to activate for each sim, this solution may help.
1-All you need to remove the previous activation, for that you need to follow the below procedures.
2.1- Install OpenSSH in you iphone using Cydia (search for OpenSSH)
2.2 Install WinSCP for Windows (WinSCP :: Download)
3. Use WinSCP to connect to iPhone
Windows Guide To Using WinSCP With iPhone
4. Follow the below steps:
4.1 Download patched lockdownd file from here
RapidShare: Easy Filehosting
4.2 Navigate to to /private/var/root/Library/ and copy lockdown folder to your desktop (for backup just in case - this you need to do)
4.3 Delete that folder from phone
4.4 Unzip downloaded patched file and upload to phone to replace the folder you just deleted
4.5 Naviagte into patched folder and make sure file pemissions are set to 644 for all files (follow the procedure in Step 3 above)
4.6 Reboot phone.With any sim..(As fone is already unlocked)
DOWNLOAD LOCKDOWN ZIP