This is strictly an IE6 problem. (Of course, if it would be a problem anywhere, you can guarantee IE6 would be involved!)
We have a site that uses jq-innerfade.js and a customized version of pngfix_map.js. After a certain amount of struggle, we got it to work acceptably on IE6, IE7, Firefox 2, while using jQuery 1.1.2. I upgraded to 1.1.4. Things continued to work fine on IE7 and Firefox. But IE6 obviously got stuck somewhere in processing the document_ready.js. I tracked it down to interference with pngfix_map.js. So I put the loading of that file on a half-second timeout (only in the case of IE6), and then the page appeared to load fine. ... until I noticed that 11 a-links in a relatively-positioned div were dead -- no hover or click activity. Oh well, I thought, I'll just use jQuery to mimic the correct behavior. I verified that jQuery was finding all the a-links. $ ( '#program-finder a' ).length did indeed return 11. I could apply various CSS to them, such as color, margins, etc. but not cursor. In addition, all attempts to apply hover and click functions had zero effect. Any idea what's going on? The page that works (using 1.1.2) is www.eimacs.com. The development upgrade page with the dead links (using 1.1.4) is at http://www.eimacs.com/eimacsstatics/skins/1/public/static/home2.htm. On that page, the link on the main image and those at the foot of the page are fine. It's the ones in the right-hand green-bordered panel that have died. (Visit the page with Firefox to see what should be happening.) Again, just to emphasize -- this is only a problem on IE6. (I know there are problems on Opera too, but we have no customers who use Opera.)