You can see this happening at http://www.archiveoflearning.net when you mouseover the "show all" link. If you move your mouse really slowly to the right, you can actually activate the mouseover on the links in the box, but if you move a bit more the whole box will disappear. This position actually coincides with the borders of the iframe below it. I've even set the z-index of the box to as high as 5000 but the iframe still inteferes. Safari is the only browser that behaves like this. I tested the page on IE6/Win, Mozilla Firebird and Camino and they all work correctly. The menu also works correctly when i remove the iframe from the page (which unfortunately is required because the client's web host doesn't support SSI or CGIs so I have to settle for a crude hack of using Blogger and an iframe). It also works correctly on any other page on the site because only the main page has the iframe.