[SLUG] where are email files kept?

[<donohueb@xxxxxxxxxxxx>]

hi slugs,
i want to save a ton of emails off a mail server, completely delete and 
re-create the mail server and then re-copy the emails back to the new mail
server and pick up the emails again.

i don't know where the email files are kept. are they in one big file or
several files.
i'm using RH6.2 and sendmail, and pine on the email server.
any help would be appreciated.
Ben