I have been using Cookie Dog for several years and it works exactly as advertised. Cookie Dog 2 is compatible with OS X (including Panther) and Internet Explorer, Safari, Mozilla/Netscape, Camino and Omniweb.
When I upgraded to Panther from OS 9 I had to manually manage cookies in Safari and it was a bit of a hassle and a time-waster. Cookie Dog does more, and better, in less time. It's worth every penny of the $10 shareware fee.