Thank you for pointing me in the right direction, Kevin. Here are the entries I plan on entering into the Zimbra crontab:
I assume these entries would run at 2:00 AM every night and append any output to the relevant new log files. Did I get these cron entries right?
# Daily spam/ham training for DSpam and Spam Assassin
* 2 * * * /opt/zimbra/bin/zmtrainsa localhost firstname.lastname@example.org acct_pass spam > /opt/zimbra/log/zmtrain-spam.log 2>&1
* 2 * * * /opt/zimbra/bin/zmtrainsa localhost email@example.com acct_pass ham > /opt/zimbra/log/zmtrain-ham.log 2>&1
Also, I realized that I was never prompted for passwords when the spam/ham reporting email addresses were created during initial Zimbra set-up. What should be entered in the "acct_pass" placeholders above?
Many thanks for all your help, Kevin!