i just looked at source code of popunder for SP2 and Firefox and have one more question:
<param name="movie" value="pop.swf?Url=pop.php&is_bright=true" />
this tag will work only if user has installed
shockwave-flash? so it isnt able to popunder until shockwave-flash is installed on computer (?)
Anyway it works great in both of my browsers...
thanks a lot smokey.