In the NUUG FiksGataMi project (Norwegian version of FixMyStreet from mySociety), we have discovered a problem with the municipalities using Zimbra. When FiksGataMi send a problem report to the government, the email From: address is set to the address of the person reporting the problem, while envelope sender is set to the FiksGataMi contact address. The intention is to make sure the municipality send any replies to the person reporting the problem, while any email delivery problems are sent to us in NUUG. This work well in most cases, but not for Karmøy municipality using Zimbra. Karmøy is using the vacation message function in Zimbra to send an automatic reply to report that the message has been received, and this message is sent to the envelope sender and not the address in the From: header.
This causes the automatic message from Karmøy to go to NUUGs request-tracker instance instead of to the person reporting the problem. We can not really change the envelope sender address, as this would make it impossible for us to discover when there are problems with the MTAs receiving problem reports. We have been in contact with the people at Karmøy municipality, and they are willing to adjust Zimbra if something can be changed there to get a better behaviour.
The default behaviour of Zimbra is as far as I can tell according to the specification in RFC 3834, which recommend that vacation messages are sent to the envelope sender and not to the From: address. But I wonder if it is possible to adjust or configure Zimbra to behave differently. Anyone know? Please let us know at fiksgatami (at) nuug.no.