Yellow Sn0w, the soft unlock created by the Dev Team is now available from Cydia or Installer. Instead of rewording what the Dev Team has to say about it, I will simply copy/paste their entire post from their blog.

I don’t like copy/pasting large amounts of texts from other sites, but in this case, I find it really necessary. I really recommend you go over to the Dev Team’s blog, read the post from there, and write a nice thank you comment.

For those of you that don’t care about the fine prints, here are the repos for Yellow Sn0w.
Cydia source: http://apt9.yellowsn0w.com/
Installer repo: http://i.yellowsn0w.com/

I will be writing a guide wrote an iPhone 3G unlock tutorial on how to unlock the iPhone 3G using YellowSn0w.

Again, please make sure to visit the Dev Team’s blog and thanks these guys for spending New Year’s Eve behind a computer screen so everyone can have an unlocked iPhone.

From the Dev Team Blog:

BASICS

  • The unlock works exclusively with baseband 02.28.00. This baseband is provided by the latest firmware update (2.2) from Apple.  You’ll need to upgrade to this release using iTunes and then use QuickPwn to activate etc. There are plenty of tutorials about this on iclarified, bigboss, and other established tutorial sites.  Because it works on 02.28.00, it is available to everyone on the planet.  This means we don’t need to unnecessarily expose holes in earlier basebands, which is an important concern.
  • The application is a small daemon that is launched on boot.  It injects the payload at boot and also whenever there is a baseband reset.  You won’t notice anything about it other than that your third-party sim now works.  It’s a small program and unobtrusive.  There is no GUI (this is by design).
  • You can add the application using the sources outlined below (coming soon). There are Cydia and Installer sources available, so use whichever you are comfortable using.
  • yellowsn0w is completely removable through Cydia, the command line, and iTunes.

DETAILS

  • There is a known issue with SIM cards that have STK (SIM Toolkit) application menus.  These menus are usually items such as “top up” “get credit” “lotto numbers” etc. These menu items confuse the application sometimes.  Removing and reinserting the SIM once after reboot (give it about 10 secs 60 seconds (with v0.9.1) after you see the slide to unlock widget) fixes this issue.  We’re working on a better fix.
  • For those of you using SIM cards without STK menus, the application has some optional arguments that will make the unlock much faster for you.  So either experiment on your own (use “yellowsn0w -h” for usage) or wait for a customization writeup.
  • After you install yellowsn0w via Cydia, you should return to the Cydia main menu then reboot your iPhone with the 3rd party SIM installed.  Wait for the slide to unlock screen, then wait 10 or 15 secs more.   If you don’t see your carrier name pop up, then remove your SIM, reinsert it, and wait 10 secs more.  This is the step we’ll be working on eliminating next.

RANDOM

  • The application is version 0.9 0.9.1.  This is considered beta software, you use it at your own risk. You know the score.
  • The application is released on a non-commerical basis.  Please do not accept pirates and scummy ripoffs of this software. We license this software for single use and in a non-commerical environment (meaning you can’t charge for it). The techniques and methods used are not to be used by third party companies. We are watching you Jody…we won’t be so forgiving this time.
  • Direct linking to the repository URLs is prohibited, please only link to this post. We will be checking referers.
  • Happy 2009 and enjoy!

The iPhone 3G is used all over the world with all sorts of SIM cards, and we almost certainly will see untested and unexpected situations.  If the soft unlock doesn’t work for you on day 1 (literally day 1, of 2009!) then please don’t panic or be impatient.  This is new territory for everyone, so enjoy the ride as much as you can 🙂

RELEASE INFO

UPDATES

  1. Soon you’ll see yellowsn0w 0.9.1 in the repos.  It uses a much longer delay to let your SIM card initialize.  If you have problems with 0.9.0, try this one and wait a full minute after you see homescreen, then reinsert sim card.  We need both success and failure reports to tune this across the world, so please be patient (but please also report result!)
  2. If you are in the U.S. and are trying this with T-Mobile, you must turn off the 3G switch in Settings.  Also if you are good with the command line, you can make it much easier by adding the line <string>-q</string> right after the /usr/bin/yellowsn0w line in /System/Library/LaunchDaemons/org.iphone-dev.yellowsn0w.plist  (that’s and advanced tip, hopefully someone will make a boosprefs type of tool for it)
  3. No PIN support yet. Remember how we said this was beta?  Well we’re still working out the flow for SIMs with PINs enabled.  Please disable any PIN you may have on that SIM before trying yellowsn0w, for now.
  4. The unlock will silently quit on anything other than baseband 02.28.00. It detects the wrong version and just quits to avoid any damage.  Please double check your Modem Firmware setting in Settings->General->About.