Are you using delta-syncrepl?I suggest you file an ITS on this issue (I can confirm I've seen it too).
I tracked down the issue and filed an ITS on it: <http://www.openldap.org/its/index.cgi/?findid=6519>
--Quanah -- Quanah Gibson-Mount Principal Software Engineer Zimbra, Inc -------------------- Zimbra :: the leader in open source messaging and collaboration