linux2BSD Big problem!

[Fatman]

We are Trying to migrate a linux mail server to a FreeBsd server.

We are using in the Linux mail server sendmail,qpopper & drac, and the BSD
server version
5.2.1 uses sendmail 8.13.1, qpopper 4.0.5 & drac.
All the aplications was installed by means of ports and work perfectly on
bsd for the created local users with of adduser or similar. Well, the
problems come when we tried to migrate the users of linux to bsd.

We have copied the content of the /var/mail of linux to the /var/mail of
bsd, watching which the file that contains the mail of each migrated user
has the owner and adapted group, but cradled we tried to read the
transferred mail from a server to another one, with qpopper we cannot. If
with webmin we tried to see the content of the mail of the user it says to
us that the user does not have mail in /var/mail. Remenber that the new mail
users who we created directly in bsd they work fine!, we see that when
creating a new user is created a file username.pop that is the one that
contains the mail of the new users. Because our server of mail is it for
several tens of domains also we have copied from the server linux to bsd the
virtusertable, mailertable, etc. and executed makemap to regenerate
access.db etc. The problem, we understand, is centered in the re-asociation
in the server bsd of each user migrated to the file that contains its mail
in /var/mail, also migrated, of the server linux  that we have described
before.

Any suggestions?

thkx a lot.