Odds are it isn’t coded right. IE has weird quircks, the key is coding it in a gecko based browser like mozilla or netscape, then adding the little hacks to make IE behave right. IE renders padding differently, thats probably the problem.
http://glish.com/css/hacks.asp
http://css-discuss.incutio.com/?page=BoxModelHack
http://www.simiandesign.com/blog-fu/2004/03/a_simple_css_hack_to_cover_ie.php
