I was looking for some process I can restrict senders to send mails to some distribution list except allowed ones. I found this link
RestrictPostfixRecipients - Zimbra :: Wiki
I am using zimbra 5.0.2
Release 5.0.2_GA_1975.RHEL5_20080130221917 RHEL5 FOSS edition
The steps mentioned in the wiki is not working. Whenever I follow the steps zimbra stops sending mails shows "451 4.3.5 Server configuration error"
Any suggestions how to make the restriction happen.
Thank you in anticipation