I also cannot use any other variation of integer other than INT (no TINYINT, for example).

I can't use TINYINT either...

I went with INT -- space not really being an issue it just seemed like the best idea.  As for the software, it works with a ton of different databases...

I think INT sounds good too.  CHAR will have to go through the code pages so INT is probably a little faster too (though the storage space is bigger).

THANKS!