Rodrigue,
with changes I've referred to 
https://svn.roundup-tracker.org/svnroot/roundup/roundup/trunk/CHANGES.txt
It makes the life of the maintainers easier, if patches already
contain some documentation or a changes entry.

Like with your patch it would be cool to know for the documentation.
what people could do to activate the benefits or migrate from
old settings.

If this is a general improvement should it be a default for new tracker
instances.