iPhone Dev Team has just released Redsn0w 0.9.7b4, which eliminates the need to install and run a separate program for usbmux.
iPhone Dev Team had released Redsn0w 0.9.7b1 over the weekend that implements the “backup plan” for iOS 4.2.1 untethered jailbreak for iPhone 4,iPad and iPod touch 4G, which is currently meant only for beta testers.
They are working overtime to fix all the issues to get it ready for the general public. They have already released Redsn0w 0.9.7b2 to fix native app crashes and Redsn0w 0.9.7b3 to fix bugs related to non-GUI programs such as Facetime, Winterboard themes, and embedded videos in iTunes.
iPhone Dev Team has updated their blog post to provide more details about the new beta version:
The fourth beta is now available (testers ONLY please!). Starting with this version, redsn0w no longer requires you to install and run a separate program for the usbmux (this was a non-trivial procedure for many). It’s okay to keep that program running if you normally use it for ssh anyway. We also think we’ve fixed a race condition in the GUI that was causing redsn0w to crash during the “Preparing JB Monte Files” step. Nothing at all has changed on the iPhone side (where the main issues are still just Bluetooth and Skype).
We would like to again reiterate that Redsn0w 0.9.7 beta is still not meant for general public so stay away until all the issues are resolved if you are not interested in being a beta tester. Redsn0w 0.9.7 beta is currently available only for Mac users, Windows users will have to wait for public release of Redsn0w 0.9.7.
If you plan to beta test it then download Redsn0w 0.9.7b4 for Mac using this link (Dev Team has advised beta testers to test it after a fresh restore). Please don’t forget to let us know how it goes in the comments and also provide your feedback on Dev Team’s blog, which will help them to iron out the issues before the public release.