Few Hours ago the iPhone hacker Musclenerd Posted in a tweet that you can jailbreak iOS 5 beta 4 using Redsn0w 0.9.8b4 .
MuscleNerd Said :
redsn0w 0.9.8b4 tethered JB released for iOS beta4 (JB app devs only please).
Redsn0w 0.9.8 was Released last month by iPhone Dev-Team to jailbreak iOS 5 Beta 1 and it was able to jailbreak iOS 5 Beta 2 and Mucslenerd confirmed That you can jailbreak iOS 5 Beta 3 by the same version of Redsn0w.
Download iTunes 10.5 Beta 3.
Download iOS 5 Beta 3.