They work in Firefox, but not IE. I think the problem is fixed in IE7, but I'm not totally sure.
There's a couple of workarounds that use Javascript, although I've never used them before so can't promise anything:
http://koivi.com/ie-png-transparency/
http://homepage.ntlworld.com/bobosola/
Hope that helps.
There's a couple of workarounds that use Javascript, although I've never used them before so can't promise anything:
http://koivi.com/ie-png-transparency/
http://homepage.ntlworld.com/bobosola/
Hope that helps.