I used redsn0w to jailbreak/unlock my 2g iPhone (US iPhone using a UK o2 sim). However since the firmware upgrade many people are telling me they are unable to call me as they are getting 'it is not possible to connect this call at this time' messages. They are also getting errors when sending texts to me. The odd thing is that there are a few people that can call me but the vast majority can. As you can imagine I am a bit worried now and really hoping someone here can help.