The UltraSn0w iPhone unlocking software has been updated to support iOS 4.0.
The iPhone Dev-Team’s has updated Ultrasn0w to version 0.9.3, allowing you to unlock your iPhone running iOS4.
The update was announced on the Dev-Team’s Twitter stream. According to the release notes, it works with all basebands from 04.26.08 through 05.13.04:
iPhone DevTeam’s 3G and 3GS software unlock, now with added PwnApple. Compatible with basebands 04.26.08, 05.11.07, 05.12.01 and 05.13.04! Thanks to @sherif_hashim and @Oranav for contributing baseband crashes.
We will have an easy-to-use unlocking how-to guide coming soon.
NOTE: This post has been edited. It incorrectly said Ultrasn0w was for jailbreaking iPhones.