Problems with style sheet fonts

I have noticed these pages (and others) http://www.w3.org/DOM/ and
http://www.w3.org/Architecture/ use a style sheet
(http://www.w3.org//StyleSheets/activity-home.css) which is rendered
incorrectly in IE 5.5 (version 5.50.4522.1800). Any text within <p></p> or
<li></li> tags is displayed as gibberish. Is this a problem with the style
sheet, which lists neither p or li as a defined style or just another MS
bug?

Thanks,

Mike Baucom