As you know Apple released iOS 5 Beta 5 two days ago , and we used to jailbreak iOS 5 Beta with Redsn0w in the same day or in the same week but till now iPhone Dev team did not release any update of Redsn0w to jailbreak iOS 5 btea 5.
In case you don’t know, most of the iPhone Dev Team along with Geohot and Chronic Dev Team’s p0sixninja are now attending the DEF CON 19 hacker conference in Las Vegas. So they might be not be able to release Redsn0w 0.9.8b5 these days to jailbreak iOS 5 beta 5 (tethered only).
You also can’t use Redsn0w 0.9.8b4 by pointing it to the beta 4 IPSW:
We launched redsn0w 0.9.8b4, selected the iOS 5 beta 5 ipsw and started the jailbreak process. It took a longer time than usual however the process did complete and we were taken to the Home screen which displayed a white Cydia icon. This usually happens after you run redsn0w to jailbreak iPhone, iPad or iPod touch tethered. So this meant that we had to do a tethered boot once redsn0w finished installing Cydia on our device. However, the device was unable to boot tethered further confirming our doubts that redsn0w 0.9.8b4 will not be able to jailbreak iOS 5 beta 5.
Stay tuned for any updates.