Internet Explorer uses Microsoft modified Java, whereas Mozilla Firefox uses native Sun Micorsystem Java - hence it has idiosyncracies. If you have articles on your website and have not disabled PDF display, they work in Firefox, but not IE. Another issue is that URL's are partially case sensitive, so if you built any links make sure they are capitalized correctly. Many times these work fine, but once in a while having a misplaced capital letter will generate a 404 error for missing page. Again, IE seems more sensitive to this.
Duh, by the way I use IE8 and only do Firefox when IE acts up....
Dave Sause
oldandfat@cox.net