> Reducing the work to merge them into the main issue.
We already have that merge functionality in the tracker, based on the example you mentioned.

> You could even have it automatically send an email to the person who created the misplaced issue. This email could tell them how to properly reply to the issue.
Indeed, the underlying problem is that users are not aware of misplaced issues. Most will notice only at some later point in time that their email has not been filed into the intended issue. Or they will not notice at all that something went wrong. An automatic notification mail about the misplaced issue would be helpful.

Actually, I am not doing the technical support for that tracker anymore - Ralf is doing that.
Ralf, can you support that? I guess such automatic warning mails would considerably reduce the work load of the tracker maintainers.