How to Upgrade to 3.0.1 and Unlock iPhone 3g with baseband 2.30.03 & bootloader 5.09, 6.02, 6.04
First you will need cydia to download fuzzyband. When fuzzyband detects your modem version it will ask you to uprade. click on upgrade:

* your screen will say OS 2.2.1
Now start up iTunes and update to the latest 3.0.1


Download the 3.0 ipsw file here
Extract the redsn0w zip file and start redsn0w.exe
Browse for the ipsw file and follow the directions.
After jailbreaking the phone, you need to unlock it with ultrasn0w.
Download ultrasn0w
Goto cydia -> manage -> sources -> edit -> add
enter http://repo666.ultrasn0w.com

return to cydia, hit done and select the new repo you just added.
Install ultrasn0w and follow instructions.

You are now unlocked!
Popularity: 6% [?]
August 26th, 2009 at 4:36 pm
[...] Originally Posted by volkspost Sorry to say, but you are stuck. The bootloader can't be downgraded and you are at 6.02. 5.8 would be the only one that allows to downgrade the baseband from 2.30 to 2.28. 2.28 would be the one that can be used with Yellowsn0w. now, theres luck. check this How to Upgrade to 3.0.1 and Unlock iPhone 3g with baseband 2.30.03 & bootloader 5.09, 6.02, 6.04… [...]
October 10th, 2009 at 5:59 pm
hi,
so is it possible to unlock your if phone if you have :
iphone 3g
OS 3.1
and bootloader 6.02 ?
thanks
October 16th, 2009 at 1:16 pm
I try searching fuzzyband downgrader version 3.1 b1 using Cydia but not found. i just found fuzzyband version 3.1gm. Can u please help me give me the direct link to download…or advice me
tq
October 18th, 2009 at 11:54 am
i tried this method but it is not working, fuzzyband only support BL 5.8 and it is not working for BL < 5.8
unfortunately i upgrade my iphone from 3.0 to 3.1.2 by Itunes . I downgraded it back to 3.0 successfully but now stuck with unlocking as 3.1.2 had upgrade my BL and BB
October 29th, 2009 at 8:22 pm
i have same question so u do.I have same bootloader can’t do anything
November 15th, 2009 at 8:53 pm
[...] How to Upgrade to 3.0.1 and Unlock iPhone 3g with baseband 2.30.03 & bootloader 5.09, 6.02, 6.04 moved to http://hydtechblog.com/2009/08/26/how-to-upgrade-to-3-0-1-and-unlock-iphone-3g-2-30-03-with-baseband… [...]
December 6th, 2009 at 11:23 am
I am definitely bookmarking this page and sharing it with my friends.