However, this version of Redsn0w (0.9.5) is not meant for iPhone users as many things such as jailbreak apps won’t work. It is targeted at developers of jailbreak apps so they can fix their iPhone apps before iPhone OS 4 is released in summer.
MuscleNerd from the iPhone Dev Team made this announcement via Twitter:
1st public 4.0b1 jailbreak .. Only JB devs til they fix their SW! iPhone3G+Mac only til more is working
iPhone Dev Team has explained the reason for releasing the jailbreak only for jailbreak app developers:
Please not that this beta is not meant for the average end-user. There are many things “broken” with jailbroken apps in the 4.0beta1 environment right now (that's the real reason we showed “Veency” in the 4.0 jailbreak demo video last week, instead of say MobileTerminal.app, which is broken!). This beta redsn0w allows the developers behind those jailbroken apps (like MobileTerminal.app!) to fix their software before the general public gets iphoneOS 4.0.
Because it's meant for JB app developers, this beta redsn0w does not perform hactivation. You'll need a properly-registered developer UDID with Apple to get past the activation screen. For similar reasons, there is no Windows version of this beta redsn0w (since apps are developed on MacOSX). Please don't pirate Apple software.
For now the first beta of Redsn0w supports:
iPhone 3G only
Mac OSX only
iPhone OS 4 beta 1 only
Dev team has also warned users who depend on a carrier unlock to avoid iPhone OS 4 beta 1 as it includes a baseband update.
With the public release of jailbreaking software for iPhone OS 4 released, it needs to be seen when iPhone Dev Team and Geohot release jailbreaking tools for iPhone OS 3.1.3 for iPhone 3GS users.
[via Dev Team’s portal]