[toivo]

I am using 3.6.8 with this mod. The only problem I have experienced happens when someone has an auto-reply rule which does not exclude the forum email address and the out-of-office message starts bouncing back and forth and it gets propagated to everyone. I managed to fix that through code that compares the incoming message with the last post from the sender.

Do have a mail server which allows you to create a rule which copies each incoming message to a separate folder? Then you can check if the duplicated messages are triggered by the same message being received twice.