Unlock iphone 3GS and jailbreak OS 4.0 beta for cydia

We have managed to Unlock iPhone 3G on the last version os 4.0. The new unlock iPhone 3G solution is easy to use and can be done in few minutes. To Unlock iPhone 3G simply download the unlock software on your computer and install it.
Geohot has posted a picture which shows iPhone 4.0 with Blackra1n icon on it, indicating that he has managed to jailbreak the new iPhone 4.0.
Dev Team member MuscelNerd has already announced that he has successfully jailbroken and unlock iPhone 3G 4.0 few days ago. Geohot is the second hacker who has now managed to unlock the latest iPhone OS 4.0.
Despite all these pictures and videos posted by Geohot and Dev Team it is still not clear if they have also managed to unlock iPhone 3G 4.0, which is crucial if one wants to use other SIM on this AT&T exclusive device.
iPhone developer team has released Redsn0w 0.9.5 for Mac. This Redsn0w allows to jailbreak iPhone OS 4.0 Beta. This Redsn0w release won’t help you to unlock or hactivate your iPhone.
So registered UDID is what you want for the activation process. So, you are requested not to update to iPhone 4.0 if you rely on an unlock. The guide given below will only be helpful to jailbreak iPhone 3G on iPhone OS 4 Beta.
How To Jailbreak iPhone OS 4.0 With Redsn0w 0.9.5
For iPhone 3GS, download iPhone OS 4 Beta.
Update to this latest firmware file: iPhone1,2_4.0_8A230m_Restore.ipsw
Open redsn0w 0.9.5 and locate the original iPhone OS 4 Beta firmware for iPhone 3G to go ahead.
Choose “Install Cydia” and click “Next”.
Now make sure your gadget is both OFF and PLUGGED IN to the PC before you click “Next”.
Connect your device in recovery mode by pressing the Power and buttons continuously.
At this point you will be presented with a screen where you will have to quickly hold “Power” button and then while holding the “Power” button, you will now have to hold “Home” button too. Now after few seconds release “Power” button but keep holding “Home” button until installation starts.
Step 7: No wait and allow redsn0w to perform its work. Once finished, your iPhone 3G will reboot automatically and you will find it jailbroken with iPhone firmware version 4.0.Have you notice that Cydia has a blank white icon and also Cydia has no sources. Now go to the Sources panel and add http://apt.saurik.com/cydia-3.7 repo. Now reboot iPhone and the regular standard Cydia logo will be there.