Package: packaging-manual Version: 2.4.1.2 are the examples for diversions are wrong, or do I miss something? dpkg-divert has to be called for an upgrade as well and for the purge of a package as well.
if [ install = "$1" ]; then
dpkg-divert --package smailwrapper --add --rename \
--divert /usr/sbin/smail.real /usr/sbin/smail
fi
if [ remove = "$1" ]; then
dpkg-divert --package smailwrapper --remove --rename \
--divert /usr/sbin/smail.real /usr/sbin/smail
fi
