MuscleNerd told on his Twitter page that he has released the first public version of redsn0w for the iPhone OS 4.0 beta 1. This isn’t currently available for the the average user, but for developers of current jailbreak applications.

This is a beta release of redsn0w targeted at developers of jailbroken apps. It uses the same pwnage2 DFU-mode exploit that we’ve been using since the 2.x days. Nothing new is revealed to Apple, and it’s not applicable to the iPad. Don’t go near it if you use yellowsn0w, ultrasn0w, or blacksn0w.

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.

Anyone other than developers of jailbroken apps porting their software to 4.0beta1 should still be using our previously-released redsn0ws for 3.0 through 3.1.3

This BETA release supports:

• iPhone 3G only (for now)
• Mac OSX only (for now)
• the 4.0beta1 FW only (for now)

YOU SHOULD STAY CLEAR OF THIS BETA SOFTWARE IF YOU RELY ON A CARRIER UNLOCK. That’s because the beta redsn0w works only if your device has already been upgraded to the stock 4.0beta1 IPSW from Apple, which contains a baseband update. If you installed that IPSW, you’ve already lost the carrier unlock until the next planned release of ultrasn0w and blacksn0w.

Download redsn0w 0.9.5 beta here.