Default profile (local) settings are not copying over to domain accoun

So I have a fresh build of Vista/w/SP1 and a bunch of programs installed. I have generic local profile that I copy over to the default profile. The machine is now joined to a domain. When some one logs in, they are validated by the domain, and a "local" profile is created for them, it has some settings from the local default account (Sidebar turned off, my computer on the desktop), but it seems that file associations are not copying over. For instance, Firefox is set as the default for HTM and HTML, on the default profile, but any domain user that logs in and clicks on a weblink gets prompted "could not perform the selected action because an internet browser could not be found". In the "set associations" in the control panel HTM and HTML are recognized as Firefox documents but the third column (Current Default) says unknown application. Is this the expected behavior? I can (as well as each user) choose FF or IE (or whatever) as the default and links will open fine, but this should be able to be set on the default profile and then carried over in my opinion (and on another computer model following the same build process...it does). Anyone have any idea what is causing this behavior?

Straytoasters