My friend forwad it to me from http://www.orbs.org/otherresource.html
a.. Qmail admins: Qmail's current version is insecure by default. Most
admins know enough to follow the instructions for securing it before putting
qmail into service, however it usually drops ORBS test messages checking for
UUCP pathing vulnerabilities - "! pathing" - into the admin mailbox. As ! is
a standard network addressing indicator, this can only be charitably
described as yet another Qmail bug. Qmail is extremely network unfriendly
and has been known to cause effective denial of service attacks on other
mailservers in its enthusiasm to deliver as many messages as possible in a
short period of time. For this reason it is best reserved for mailing list
server purposes only.
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I need to know the real stuff cause I'm going to build and email server
using qmail for an ISP
Thanks all for the comment
