Thanks Eleni!!! Everything is working fine and actually a lot faster than before(My MMS was sent pretty quickly)!
Also my MMS wasn't working due to bad settings. I finally got to send my brother a picture of my yankees' cap

He is a Phillies fan :P
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So people who cannot get their data/mms working; here's what to do:
For DATA:
1] Change your Cellular Data APN to: internet2.voicestream.com
FOR MMS for (2G):
1] Add this source to the repo:
Code:
http://www.sinfuliphonerepo.com
2] Install "Enable MMS for 2G & 3.0 FW -OR- Enable MMS for 2G & 3.1.2 FW" via Cydia
3] REBOOT
4] Go to Settings -> General -> Reset Network Settings
5] REBOOT
6] Enter the following for MMS Settings:
APN: epc.tmobile.com
Username: BLANK
Password: BLANK
MMSC: http://mms.msg.eng.t-mobile.com/mms/wapenc
MMS Proxy: 216.155.165.050
MMS Max Message Size: 24000000
MMS UA Prof URL: http://wap.sonyerricsson.com/UAprof/W800iR101.xml
7] You should be good to go with MMS now, anyone can chime in if I made a mistake.
- - - E D I T - - -
Try this to set a different APN for your MMS and for your Data:
1] Go to on your iPhone:
Code:
http://unlockit.co.nz
2] Tap Continue.
3] Tap "Custom APN"
4] In the Carrier dropdown menu choose the 1st 'US T-Mobile' option.
5] Then it will automatically put in 'internet2.voicestream.com'.
6] Now it 'Create Profile'.