iPhoneSimFree has just released its new software version of dsimlockage, it's about the version 1.7 which would be designed exclusively for firmware 1.1.1.
With the release of a new jailbreak / activation by community development teams, there is no longer a need to downgrade to 1.0.2. SimFree 1.7 is specifically designed for firmware 1.1.1. The brilliant work combined with the developer teams means that with SimFree 1.7 it is now possible to unlock it in less than 10 minutes. We strongly recommend that all of our resellers offer this new jailbreak method. Please note that if you have already unlocked your iPhone using a previous version of SimFree, there is no need to update it.
iPhoneSimFree also explains on its site how jailbreak the iPhone to place the SimFree software on the iPhone.