AIX 3.2 as shipped is configured to only send mail to mail addresses
which include a host name.  Many organizations use a mail address whose
"host name" part is not a host name (technically an MX name).  To change
the configuration of the AIX mailer, login as root.  Then edit the file
/etc/sendmail.cf to remove the comment marker ("# ") at the beginning of
the line which reads:
    # OK MX

Now rebuild the machine readable form of the configuration with
    sendmail -bz

and finally restart signal sendmail to load the new configuration by one
of the following:
     reboot
or
     stopsrc -s sendmail
     startsrc -s sendmail
or 
     kill -1 `cat /etc/sendmail.pid`

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