Active Menu link does not highlight in IE.

I stumbled upon this problem in my own project and I realized that it also affects Drupal.org.

In the Drupal created menu blocks like "Book Navigation" and "Navigation" the active/selected link does not change colors! Screenshot attached. This problem only affects Microsoft Internet Explorer. It works fine in Netscape and Mozilla.

Looking at the page source, you can see that drupal is creating the following HTML for a seleced item on a menu:
<li class="leaf"><a href="/admin/modules" class="active">modules</a></li>

This is not a valid use of the class attribute (in the MS IE world):
I fixed the problem in a custom block by passing an id=active rather than class=active. Then I passed the id within the 'li' tag instead of the 'a href' tag.

<li class=leaf id=active><a href="/flexinode/table/1">Community Participation</a></li>

I haven't looked to see how hard this would be to fix in Drupal Core (menu.module), but it is an important navigational issue that should be addressed in the upcoming releases.