After installing Zimbra 5.0.x on my Debian Etch 4.0 server some of my shell scripts couldnæt send mail anymore. The reason to this behaviour was that I hadn’t removed the Exim mail server package, and I wouldnt do it either.

The solution to this problem was to remove exim or locate the sendmail binaries and remove the symlinks to exim as emailer client and create symlinks to Zimbra’s Postfix sendmail binary. I did the latter

# whereis sendmail
sendmail: /usr/sbin/sendmail /usr/lib/sendmail

# rm /usr/sbin/sendmail
# ln -s /opt/zimbra/postfix-2.4.3.4z/sbin/sendmail sendmail
# rm /usr/lib/sendmail
# ln -s /opt/zimbra/postfix-2.4.3.4z/sbin/sendmail sendmail

Now my scripts can send e-mails as expected.