Related to this:

- I often create issues that I assign to myself. Here the status
  "unread" doesn't apply, because I already read it.

- Users often create issues without assigning them to anyone, because
  it is not their job to do that. When I'm assigning the issue e.g.
  to ber with a comment like "Bernhard, can you take care of this?"
  This sets the status from unread to chatting, but the one who would
  do the real work on the issue did not read it.
  Or a second user would say "I have the same problem", causing the
  status to be set to chatting.
  So my question is: Should chatting (optionally) only be set if the
  message is sent by the person in the assignedto field?

(Regarding detectors/config.ini: I'll comment on the -devel list)