Canon Digital Rebel XT Numbering Problems

This past weekend I ran into some problems with my Rebel XT not numbering photos correctly. It appeared that the camera was numbering photos fine at first, but apparently I put a card in that I didn't format before shooting a photo, so that card started off with a photo number in the 6000s. On sunday the counting started back over around 100. I'm going to have to mess with some settings, see what the best method for number my photos is. With my Rebel 300D I always just let it do the continuous numbering, I don't think I'll do that anymore though.