After the jailbreak comes the unlock. And it only took a few days this time. Welcome the iPhone 4 software
unlock, which will allow you to use your device with any SIM (well, microSIM, actually) card. You only have to pay Cydia a short visit and to download the tool you need, ultrasn0w 1.0-1.
It was high time some good news involving theiPhone 4 surfaced. Luckily, this time we're not going to talk about antennas, reception issues or anything like that.
The latest version of the ultrasn0w, ver. 1.0-1, manages to break the chains of not only iPhone 3G and 3GS (basebands 04.26.08, 05.11.07, 05.12.01 and 05.13.04) but also of iPhone 4 (baseband 01.59.00). Keep in mind that you have to jailbreak your phone first in order to be able to proceed to step 2, the unlock.
So, head for Cydia, type ultrasn0w (if needed, add the repo: repo666.ultrasn0w.com) and once the download is complete, start the application and let your iPhone work with any microSIM card out there.