iPhone 3G w/4.1 Unlock Unable to Connect to T-Mobile

[CuriousCurmudgeon]

I just did a jailbreak and unlock on my iPhone 3G to use on T-Mobile, but am unable to actually connect to the T-Mobile network. Before moving on to the T-Mobile-specific forum I wanted to make sure I had actually done the jailbreak/unlock correctly.

Info
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iPhone 3G
Firmware: 4.1
Baseband: 05.14.02

I used the guide at Jailbreak iOS 4.1 with PwnageTool 4.1 [How to Guide] | Redmond Pie to jailbreak with PwnageTool 4.1 and unlock ultrasn0w 1.2. After using ultrasn0w I am still unable to connect to T-Mobile. Going to Settings->Carrier gives me an error message "Unable to load network list".

I had problems finding out if I can even unlock with my baseband, but was under the impression that it now worked. This is the first iPhone I've unlocked or jailbreaked so I've been drowning in contradictory guides and different tools. Things seem to change rapidly.

Thanks for any help.

[Simon]

That baseband cannot be unlocked. If you want to unlock you need to update to the ipad baseband.

[CuriousCurmudgeon]

That baseband cannot be unlocked. If you want to unlock you need to update to the ipad baseband.

Thanks. Is this guide still accurate to update the baseband to 06.15.00? (Basically download both the iPad and iPhone firmwares and then run PwnageTool.)

Update iPhone 3G / 3GS to 06.15.00 Baseband

[Simon]

You can just use redsnow 0.9.6rc7 to do it faster and easier if you want, and no need to download the ipad firmware itself.