[Mailman-Users] gmail "Multiple destination domains" error

[Andrew Daviel]

I have a mailman list running on Linux CentOS 5 with sendmail 8.13.8. 
Generally, everything works (I believe/hope).

Today I got a bounce action notification. When I looked at it,
there's a regular DSN e.g.

   ----- The following addresses had permanent fatal errors -----
<xxxx at utvinternet.com>
     (reason: 550 5.1.1 <xxxx at utvinternet.com>: Recipient address rejected: User unknown)

OK so far. Then in the same message I see

    ----- Transcript of session follows -----
... while talking to gmail-smtp-in.l.google.com.:
>>> DATA
<<< 451-4.3.0 Multiple destination domains per transaction is unsupported. 
Please
<<< 451 4.3.0 try again. r2si3773706igh.8 - gsmtp
<user_1 at gmail.com>... Deferred: 451-4.3.0 Multiple destination domains 
per transaction is unsupported.  Please
<<< 451-4.3.0 Multiple destination domains per transaction is unsupported. 
Please
<<< 451 4.3.0 try again. r2si3773706igh.8 - gsmtp
<user_2 at gmail.com>... Deferred: 451-4.3.0 Multiple 
destination domains per transaction is unsupported.  Please
<<< 451-4.3.0 Multiple destination domains per transaction is unsupported. 
Please
<<< 451 4.3.0 try again. r2si3773706igh.8 - gsmtp
<user_3 at gmail.com>... Deferred: 451-4.3.0 Multiple destination domains 
per transaction is unsupported.  Please
etc.

When I grep the mail logs, all the deferred messages to 
gmail-smtp-in.l.google.com (74.125.192.27) are xxx at gmail.com,
i.e. all to gmail.com

However, I've also got several users on googlemail.com, also using 
74.125.192.27. Those messages went through OK, and seem to be associated 
with the ID r2si3773706igh.8


Has anyone else seen this ? Does Google not like sendmail anymore ?


A bit later, I see things like
to=<user_10 at hotmail.com> dsn=4.3.1, stat=Deferred: 452 Too many recipients
to=<user_11 at hotmail.com> dsn=4.3.1, stat=Deferred: 452 Too many recipients


Again, does Hotmail not like sendmail ? Is there something I should tune, 
or is this just normal mail behaviour and it will be dlayed till the next 
queue run ?


-- 
Andrew Daviel, TRIUMF, Canada