XSL-List admin query

i have a problem setting rules to detect and file these messages away from
my inbox. most messages have a trailer " XSL-List info and archive:
http://www.mulberrytech.com/xsl/xsl-list" which i can match on, but some
don't.

why!? can this be "fixed". or can we have something like  inserted
in the front of every subject line to aid auto-filing of messages.

thanks

mark

ps i can't use the "to" field because again there are exceptions due to
people using different aliases for the list address. (i'm using microsoft
outlook which isn't clever enough to look beyond the email alias to the
actual "to" address)


 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list