Possible solution attempts:

1. finding a way to initiate a FULL recovery (including baseband!) with FW 1.1.1

Right now, it seems that everything but the baseband fw is updated on previously software unlocked iPhones, causing the well known IMEI problem

2. finding a way to restore/downgrade the FW 1.1.1 updated iPhone to a FULL RECOVERY FW 1.0.2 update (incl. baseband fw)

This may be the easiest to achieve way to fix the problem because once the baseband fw is re-written on FW 1.0.2, the software unlock is gone. Theoretically this should also allow a "clean" FW 1.1.1 update without any more IMEI and activation issues

CAUTION: you still need a way to hack activation, both above (possible but not yet found) methods allow a FW 1.1.1 activation only using an official AT&T activated iPhone SIM card (contract or GoPhone contract)