It would be nice to have a plugin to delete old PMs
I need it too and might write it.
Would be fairly easy with the task system.
I did some research. It shouldnt be hard. Task system is enought, just to set how many days before delete old PMs.
Also there should be a setting for not deleting unread messages (but - it is complicated, because some users never come back online and their pm box is full with notifications from forum etc.) -> maybe delete unread messages after 60 days
OK, I will create a simple plugin. Give me some time (my first one)