I finally figured out how to do this but it requires using MobileTerminal.
Adding this to biteSMS would totally rock !

Guide: http://www.hackint0sh.org/forum/f127/73876.htm

Flash SMS will be great.
+1 to this idea

I thought the iPhone does not have a Flash plugin ?

flash sms != adobe flash

No it’s called flash sms because it will suddenly appear on you screen. Operators generally uses this if you are useing Prepaid(credit) line. It’s shown like this.
http://img38.imageshack.us/img38/4540/img0006a.png

Hmm.. and what is the benefit of such an SMS over a normal one ?

Yeah seems like it takes just as much time to recieve as a normal text message

And you cannot save it.. not so interested now.