I just created a site using Atahualpa 3.6.4 which has a header widget area defined in the upper right corner of the header. The header configuration looks like this:
<widget area creation code>
So, it's basically just a banner, menu and widget area containing two text widgets. This renders fine in IE8 and Firefox, but gives IE7 heartburn.
The header widget area is floated right and positioned relative to the header container. IE7 honors the widget positioning and pushes the banner to the left by the width of the widget area. This causes the site banner to be shifted to where only half of the graphic can be seen.
I was able to get the banner to display completely by adding a width: 100% attribute to the CSS, but this causes IE7 to shove the banner down so it's no longer lined up with the header widget area. If you go to the site, you'll see what I mean:
View it in Firefox or IE8, then check out IE7 to see what it does. I'm not the world's foremost CSS expert. I've tried what I can think of to try and this is the best I've been able to get it to look in IE7. Any ideas would be appreciated.
Btw, the site is running WP 3.1 at the moment.