PAM userdb database permissions

["Simon Atack (Uni)" <S.Atack-97@student.lboro.ac.uk>]

I am using the userdb PAM module to authenticate smtp for relaying, what
user and group do i need to set the database to?

For obvious reasons i dont want to set it to 444 (but at the minute i have
to get it to work)

Thanks

Simon Atack