I'm afraid i know nothing about phones that are JB'n, maybe someone else can advise you on that, it is strange though, have tried turning imessage off and on again?I tried that and the old ones That I deleted and started new ones well when it rebooted it deleted the news ones and put back some old messages and like my GF in the history chat pages the old chats came back again even tho I deleted it
its very strange you think I should go back and restore in iTunes and jailbreak it again ?