Transfer User Profile

I created a new Windows 2003 domain with a DC. I have some
Windows 2000 Pro in a workgroup. I join them in to the new
domain. When I first time log on the original user into
the domain, some PCs popup windows and say something
like "do you want this local user profile transferred to
domain profile?", I click yes, and then log on the new
domain with the transferred user profile. But some others
PCs do not ask this and use Default User profile logging
on the new domain. How come? Thanks.