Problem using T-mobile prepaid on iPhone 3gs

[TheRealDeal]

I have been using my 1st generation iPhone with T-mobile for months now and I've loved it. Recently a friend gave me their iPhone 3gs which is a big upgrade and I want to use it with my T-mobile prepaid account. The process was so surprisingly easy with the iPhone 2g. Now with the 3Gs it's been a nightmare. I need to know what I'm doing wrong:

-I jailbroke my phone with the most current Redsn0w software for mac OS.
-I then unlocked it using ultrasn0w on my iPhone.
-Then I updated the Network settings for T-mobile with these settings:

Cellular Data:

APN: wap.voicestream.com


MMS:

APN: wap.voicestream.com
MMSC: http://mms.msg.eng.t-mobile.com/mms/wapenc
MMS Proxy: 216.155.165.50:8080
MMS Max Message Size: 1048576
MMS UA Prof URL: http://www.apple.com/mms/uaprof.rdf

Still my iPhone says "Searching..." I have yet to see it say "T-mobile" or been able to use the phone.

Any ideas??

[vyvxguy]

Try using APN:

APN: epc.tmobile.com


If that fails, try same for APN,

but change MMS to:

APN: epc.tmobile.com

[TheRealDeal]

Try using APN:

APN: epc.tmobile.com


If that fails, try same for APN,

but change MMS to:

APN: epc.tmobile.com

nothin... still the same

I have 5.0.1 version on the iPhone btw...

and my iPhone isn't the newer fixed model

[IFIX77]

You probably need a data plan with the 3GS. I have seen these run on Simple Mobile and H20. Good luck!

[TheRealDeal]

ah crap. really?

Has anyone used a 3gs on the prepaid plan?

[MrWHOx]

You do NOT need a monthly subscription. Nobody here has even asked you what baseband firmware you have. If your baseband is a newer version that is unsupported by ultrasn0w, then you simply cannot soft-unlock. If that is the case, you MUST purchase a Gevey SIM adapter for your iPhone. I've been using t-mobile prepaid on the iPhone 2G, 3G, 3GS, and now iPhone 4, for over 3 years. I've worked with my fair share of devices and the only instance where a prepaid SIM couldn't be used on an iPhone was when the SIM slot pins were scraped off by the SIM tray.

[TheRealDeal]

Yeah I didn't believe him. I got it working. Here's the post:

newer iPhone 3Gs downgrading

[1bri982]

Ok so I have a Iphone 3gs that I am going to unlock. I have the proper baseband and know I can do it but my question is is there anyway to know that it worked for sure without an active tmobile sim? i have an unactive tmobile prepaid sim but I dont want to activate it until I know im good to go.. so if i put the sim in the phone after its unlocked can i look in settings to check just to make sure its reading it? thanks guys

edit:why am i up this early? 130am eastern