I made this quick 12sec/600KB screencast to help illustrate what's happening:
There is a hidden div that contains the fieldset. The slide is applied to the div.
In Firefox, the element that has the slideDown/SlideUp effect applied works fine.
In IE7, the element just appears, then the elements around it slide (which appears broken)
The fieldset element has a position:relative property (which is needed for fixing CSS bugs on the legend tag)
If I remove the position:relative property, slideUp/slideDown works fine in IE7 (but breaks the legend tag)
Is there a way around this without having to remove the position:relative property?