Unfortunately, this is not our experience - although it is possible the message is just a distraction. slapd stops all syncrepl, and responding, until they call us to restart it.
Interesting, I wonder if the BDB database has corrupted. Have you tried rebuilding the database(s) on the system via slapcat/slapadd?
--Quanah -- Quanah Gibson-Mount Product Architect Symas Corporation Packaged, certified, and supported LDAP solutions powered by OpenLDAP: <http://www.symas.com>