I have searched and found a lot of solutions but for 2g phones or older and have found nothing that has fixed my problem.

Under Settings->General->Network
I have no Cellular Data Network tab. I did a few days ago until something happened and it disappeared. Most likely from me trying to get MMS to work on my phone. I have an iphone 4, firmware 4.0.1 jailbroken with Jailbreakme.us

My SMS works fine, calls work, etc. But I have no MMS or Facetime either. I've been trying for 3 days to fix this but nothing I seem to do will fix this. I can't find an updated ipcc file (nor know how to install one to my phone) for my carrier. T-Mobile US.

Under my "ABOUT" section of the iphone the Network claims "T-Mobile" which is correct, although down below the Carrier says "Not Available". Can anyone help fix these problems so I can send and receive MMS and use facetime? THanks