Problem with multiple lists being addressed in one mail

This works so far, but the newly created forum topics need to show up in two different forums. This works too, but forum.module then displays "this topic has been moved" for one of the groups.

We currently try to maintain a 1:1 relationship between mails and created nodes. We could break this up and let each group have its own node, but this would create problems with threading.

Needs discussion.