README.VHOST is the description of the what, who, why, and how.
The mailman-2.1.7-*.patch files are extracted from the git repository at
http://git.n-dimensional.de/mailman-virtualhost.git/
(currently off-line, will return in 2008-01)
The authoritative source is the git repository (will (2008-01-16)
be migrated to bzr as mailman upstream uses bzr now).
The vhost branch has been based on the Mailman 2.1.7 release with
Tokio Kikuchi's mailman-2.1.7-patch-20060114.txt patch (#1405790).
This means that the patches from the 2.1.7 release and
from the 2.1.7 release + 20060114 to the vhost branch are actually
useful, while the others are just for convenience.
The vhost branch will (2006-03-10) probably be ported to 2.1.8 first,
then to the 2.2 branch.
The mailman-vh-2.1.[57].patch is the "true virtual hosting" patch from
[ 943827 ] true virtual hosting patch for 2.1.