Just would like to post that I just experienced the same problem on my unlocked Nexus S on the Cincinnati Bell Wireless / CBW. Had to go to *#*#4636#*#* and enter the Hex value for the CBW SMSC # (+15132400140) which = 07915131420041F0 . I used this site which I found on another forum to calculate it: Online PDU Encoder and Decoder | Open Source @ twit88.com.