Because mine have. For some reason my iPhone 3G doesn't like sending the first text message of the day to my girlfriends phone which is also on o2. The second, third, fourth, millionth text message sends fine though. It's just that first text message after that period of quietness through the night when i'm sleeping. She never gets the text and it gets deducted in my inclusive allowance. It is rather weird, but it started after the 2.2 update. I've tried a full restore to no avail. I even gave o2 a ring and they said my account was fine and it must be a problem with my phone. I'm just curious if anyone else has had this problem? And no, it's not jailbroken. I'm thinking of taking it back to a Apple store rather than Carphone Warehouse. I'd rather not have some kid in a suit shrug their shoulders and try to sell me another iPhone.