migration to a new server --> permissions in /var/www/virtual

[soomon]

hi,

i have ispcp running on my server. now i want to move to a new server.
so i installed ispcp and copied the databases and content of /var/www/ to the new server with scp.
then everything belongs to root....
but I have to copy the permissions, too, because on the old server most things belong to www-data or vuxxx.
then i tried to tar everything on the old server and untar on the new one.
that also didn't help.

how do i move the files correctly?
a friend said that the permissions of files could be bound to the user id's instead of the usernames???

what do i have to do?

thanks & greets,
soomon