Is anyone having or know of a solution for this?

I have a iPhone 3G on XT prepay and it excelent, Though over the last few weeks ive had a few instances where i've recieved agoup of sms's at the same time.

Timestamps are over the last 3-4 hours tho in this time i have normally had txt conversations or actually been on the phone and then an hour or so later ill recieve 11 or more txts at the same time.