I'm designing a browser game and am using some JavaScript to keep track of the active race (dwarf, elf, etc). I wrote a little function that will disable the button of the race just clicked and re-enable the previous button. It works great until I place it in a <form> tag. I don't know enough about JS to understand why it does this.

http://www.kriona.net/dml/form.html (doesn't work)
http://www.kriona.net/dml/noform.html (works)