adding some lines into an existing conf file - without diff

[m96 <m96@gmx.li>]

hi,

i just wanted to ask for help.

i'm trying to build a deb pkg for a pam module and i need to add "auth"
and "session" lines to the already existing /etc/pam.d/login file. is
there a debian tool for this or do i have to do a dirty hack?

i can't use patch because every login file could be different and i
don't want to bork the login file.

thanks for any hints.
alias m96.