/usr/share/prayer/templates/cam/rm.vars is in prayer-templates-src 1.3.5-dfsg1-4build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 | # $Cambridge: hermes/src/prayer/templates/cam/rm.vars,v 1.1 2008/09/16 10:52:45 dpc22 Exp $
$type mailbox
$name Mailbox name
$g_cmd rm
|