CSS bug report

I have the following bug that occurs in IE 5.1 Mac. In NS 6.2 everything 
works as intended. I have attached the CSS and the XHTML info. The bug 
is that when I try to "fix" the positions of the header and navbar the 
"link attributes" for the page cease to work. Mouseovers do not 
function, the mouse pointer no longer changes, and the title is no 
longer displayed while hovering. The links still work but a user would 
not be aware that they were links. I changed the position of the navbar 
to absolute and left the header fixed. The bug continued. I then 
reverted back to absolute positioning for both elements and the link 
attributes function normally. The CSS validated. I am hand coding in 
Adobe GoLive 6.0. In GoLive preview everything functions as expected. 
Another problem that occurs is that the SWF nested in the header scrolls 
regardless of the positioning information for it or the parent. This 
occurs in both IE and NS. Any information would be helpful as this is a 
commercial site and I want to use it to educated other graphic artists 
as well as clients.

Thank you
Jim Siburt
Web Design
jsiburt@mac.com