HTC Desire :: Send A Text Message While There's No Coverage?

I live in a sort of remote area and my mobile coverage is kind of dodgy. This normally isn't a problem, but if I send a text message with my Desire while there's no coverage, it won't send at all. As in, even if I go outside and hold it in the air to get some bars, it will not automatically send the message from an outbox or whatever. The message shows up in the message thread, but I get no confirmation SMS.Even weirder still, if I've sent a message to a number while I was out of coverage, I can no longer send texts to the number even if I've got full bars. No confirmation, and when I talk to the person later, they didn't get it.