I'm a bit stumped here...

Check out the pages at http://www.northsouthshootout.com/

All the links should be "underlined" with a dashed border. This works on most every modern browser I've tested the site with, but with my partner's older Internet Explorer (5 I think) most of the links don't show a dashed underline, but some do.

Any clue as to what's determining whether it shows or not?

Here is the relevant CSS:

Code:
a { color: #1B4960; 
	text-decoration: none;
	border-width: 0 0 1px 0; 
	border-style: none none dotted none;
	padding: 0px 0px -1px 0px; }