Downloaded that Dreamweaver extension (thanks shags!) and replaced a couple of the mouseovers that I'd put in with DW's regular Behaviors panel. They worked--in both IE and Netscape--until I moused over one of the earlier, unreplaced links. That stopped any and all info from being displayed in the status bar. So I replaced all of the mouseovers with the new extension, and it's working fine. IE, Netscape and Mozilla all display the status bar message as desired. If Cleo or anyone else has a chance to take a peek with a different browser and/or OS, I'd be interested to see if this extension creates a workable mouseover across the board.
mouseover test page
It's my 404 page for smutmanor.com, but don't worry. No pop-ups, redirects, or anything cruel. Just links. The first banner (for Smut Manor) is a regular link--no mouseover. All the other banners have the new code.
Thanks to everyone for the input!
Lee