I am running ZCS version 4.5.10 on an Apple G5 Server Dual 2.3 GHz with 4 GB of RAM running Mac OS X 10.4.11. I have followed the instructions for restricting delivery of mail to a distribution list and achieved success the first time. After editing the permitted_senders file to add additional authorized senders and running postmap on the file, postfix returns the following error:
fatal: open database /opt/zimbra/postfix/conf/protected_recipients.db: Invalid argument

Now, even configuring the restrictions from scratch returns this error and the postfix subsystem becomes unresponsive.

Any input on this would be greatly appreciated.