+* REDIRECT aliases don't work with `n' option.
+
+ If you have option `n' set when you use newaliases and have
+ REDIRECT addresses in your aliases file, you'll get the error
+ messages during the newaliases instead of when email is sent to
+ the address in question. The workaround is to turn off the `n'
+ option.
+
+* MX records that point at non-existent hosts work strangly.
+
+ Consider the DNS records:
+
+ hostH MX 1 hostA
+ MX 2 hostB
+ hostA A 128.32.8.9
+
+ (note that there is no A record for hostB). If hostA is down,
+ an attempt to send to hostH gives "host unknown" -- that is, it
+ reflects out the status on the last host it tries, which in this
+ case is hostB, which is unknown. It probably ought to eliminate
+ hostB early in processing.
+
+* NAME environment variables with commas break.
+
+ If you define your NAME environment variable to have a comma
+ (e.g., ``Lastname, Firstname''), and you are using the $q definition
+ that uses ``name <address>'' format, sendmail treats the first and
+ last names as two addresses, thus producing a bogus From line. You
+ can work around this by changing the $q definition to use
+ ``address (name)''.
+
+* \231 considered harmful.
+
+ Header addresses that have the \231 character (and possibly others
+ in the range \201 - \237) behave in odd and usually unexpected ways.
+
+* DEC Alphas (OSF/1 1.3) sometimes time out on sending mail.
+
+ I have one report that DEC Alphas acting as SMTP clients sometimes
+ will apparently not see the "250 OK" message in response to the
+ dot that indicates the end of the message. This only happens if
+ the message is run from the queue -- if it gets through on first
+ try, everything is fine. I have been unable to reproduce this
+ problem at Berkeley.
+
+* accept() problem on SVR4.
+
+ Apparently, the sendmail daemon loop (doing accept()s on the network)
+ can get into a wierd state on SVR4; it starts logging ``SYSERR:
+ getrequests: accept: Protocol Error''. The workaround is to kill
+ and restart the sendmail daemon. We don't have an SVR4 system at
+ Berkeley that carries more than token mail load, so I can't validate
+ this. It is likely to be a glitch in the sockets emulation, since
+ "Protocol Error" is not possible error code with Berkeley TCP/IP.
+
+ I've also had someone report the message ``sendmail: accept:
+ SIOCGPGRP failed errno 22'' on an SVR4 system. This message is
+ not in the sendmail source code, so I assume it is also a bug
+ in the sockets emulation. (Errno 22 is EINVAL "Invalid Argument"
+ on all the systems I have available, including Solaris 2.x.)
+
+* Sending user deletion not done properly in :include: lists.
+
+ If you don't have the "m" (me too) option set, then a person
+ sending to a list that contains themselves should not get a copy
+ of the message. However, if that list points to a :include: file
+ that has one address per line, this will break, and the sender
+ will always get a copy of their own message, just as though the
+ "m" option were set.
+
+ You can eliminate this by adding commas at the end of each line
+ of the :include: file.
+
+* Excessive mailing list nesting can run out of file descriptors.
+
+ If you have a mailing list that includes lots of other mailing
+ lists, each of which has a separate owner, you can run out of
+ file descriptors. Each mailing list with a separate owner uses
+ one open file descriptor (prior to 8.6.6 it was three open
+ file descriptors per list). This is particularly egregious if
+ you have your connection cache set to be large.
+
+(Version 8.18, last updated 3/14/94)