repository_sync_per_request seems to be ignored with multiple hg repositories

[vincent@…]

I have Trac 0.12 running. Four Mercurial repositories are configured:

[repositories]
.alias = suave
.hidden = true
suave.description = This is the ''main'' project repository.
suave.dir = /var/lib/hg/suave
suave.type = hg
suave.url = http://smooth.applied-tactical.org/hg/suave
m3django.description = m3-django
m3django.dir = /var/lib/hg/m3-django
m3django.type = hg
m3django.url = http://smooth.applied-tactical.org/hg/m3-django
butane.description = butane
butane.dir = /var/lib/hg/butane
butane.type = hg
butane.url = http://smooth.applied-tactical.org/hg/butane
environments.description = django-environments
environments.dir = /var/lib/hg/django-environments
environments.type = hg
environments.url = http://smooth.applied-tactical.org/hg/django-environments

No commit hooks or other hooks are set up. Any commit done on any of the repositories shows up immediately in the timeline. This behavior is the same with the following settings:

• repository_sync_per_request not mentioned at all
• repository_sync_per_request = foobar
• repository_sync_per_request = butane, suave

Adding a new repository also doesn't require django-admin resync, its changes appear instantaneously in the timeline. If this is intended, it should definitely be documented.