It's broken. It never did work right because Microsoft
didn't code it properly and then never fixed the bug. A
fix and full explanation are he

http://www.jsware.net/jsware/xpfix.php5#folfix

(I also wrote a fix for Vista/7 at one point, which is
slightly different from XP. But in my limited experience
with Vista/7 it appears that MS finally fixed the bug.)