Unresponsive script when managing categories

I’m not getting a reply in my post in the WordPress.org forums, so I’m bumping it by posting here as well.

When I try to delete empty categories, Firefox [1.5.0.1] will hang for a few seconds before displaying a warning:

“A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.”

I’m running WordPress 2.0.2.

Thanks!