Tabbed Browsing in Win2000 Domain?

Just noticed that my users can’t use tabbed browsing with IE7, and it seems to be because of GP from our Win2k Server. If I log the user out and log on as the Administrator, tabbed browsing works fine.

And no, rolling out Firefox to all my users isn’t the solution I’m looking for…

I’ve looked at the existing GPOs and cannot find anything pertaining to tabbed browsing. Of course, 2k Server predates IE7, so I don’t think anything would be there natively.

What must I do to enable tabbed browsing for our 2k AD domain clients?