Heres my story. I purchased an iphone over kijiji locked to rogers and jailbroken to 3.1.2. During my days of owning it i found that the signal would drop randomly to 0 bars and proceed to "searching" to look for a network.. Ive looked this issue up plentiful over these forums and found that blacksnow seemed to be the culprit. After going through cydia i found that blacksnow was installed so i uninstalled it. I thought the problem was solved but a couple of minutes later after using apps that use 3g the connection dropped again. I dont know how this phone was jailbroken. its the 3gs with the old bootrom. ive never had this issue with my 3g phone. I restored again using redsnow and still same problems. What do you suggest i do? believe me it has nothing to do with the network.