Only use RQ 2.4+ and its cron capabilities.

test_project/test_project/cron_config.py

@@ -0,0 +1,8 @@
+from rq.cron import register
+
+from modoboa.core import jobs as core_jobs
+from modoboa.admin import jobs as admin_jobs
+
+
+register(admin_jobs.handle_mailbox_operations, queue_name="dovecot", cron="* * * * *")
+register(core_jobs.clean_logs, queue_name="modoboa", cron="0 0 * * *")

test_project/test_project/settings.py

@@ -385,6 +385,7 @@ LOGGING = {
         },
         "modoboa.admin": {"handlers": ["modoboa"], "level": "INFO", "propagate": False},
         "modoboa.dns": {"handlers": ["syslog"], "level": "INFO", "propagate": False},
+        "modoboa.jobs": {"handlers": ["syslog"], "level": "INFO", "propagate": False},
         "django.server": {
             "handlers": ["django.server"],
             "level": "INFO",