And no, d33zY, it had nothing to do with refreshes.

Well it does for my version of IE. As an experiment, go to Tools>>>Internet Options>>>General Tab>>>"Settings" in Temporary Internet Files>>>>And change "check for newer versions of stored pages" to Never. Then fill out a BBS reply and before you hit submit go browse some other sites for a few minutes, and then hit Back until you get back to your untouched form.

The reason IE clears the forms sometimes when you hit the back button, is because sometimes it uses the cached version of the page, and sometimes it downloads an updated version. Perhaps it relies on a timeout. I don't know.