Applenberry finally released a new version of Gevey Sim Ultra which can unlock iPhone 4S iOS 5 and 5.0.1 baseband versions 1.0.11, 1.013, 1.0.14. The new version does not unlock iPhone 4 04.11.08 yet, but they promised that a new version will be available soon.
Here is a video tutorial for the new Gevey Sim Ultra:
The new Gevey Sim is available via applenberry on their site. It is somewhat expensive, but it does a good job.
Order Gevey Sim ultra for $54.99: http://applenberry.com/store/gevey-sim/gevey-ultra-1