lost mailing-list after transferring to new server

Hi,

All mailing list (using mailman) are dissepear after transfering to new server.

The list name is on my clients' cpanel page. But when
they click on it, mailman responds with No such list listname_domain.com.

Anyone has the same problem? How to put the list
back into mailman web interface? I know the lists are
transferred to the new server since the files are there.

Thanks.