Earlier today, it was reported that AppStore applications didn't work on iOS 5 beta 3. A recent sn0wbreeze 2.8 update supposedly did not have this issue because it had an updated kernel. MuscleNerd (@MuscleNerd) just tweeted out that redsn0w was updated as well to fix this sandboxing issue with AppStore applications on iOS 5 beta 3. The article that was posted earlier about jailbreaking iOS 5 beta 3 with redsn0w is now out of date; that version of redsn0w does not fix the sandboxing issues on iOS 5 beta 3.

redsn0w 0.9.8b2 (Mac)
reedsn0w 0.9.8b2 (Win)

Source- modmyi