Fix for  3300 : Cannot start server if backend of replicated suffix is disabled

If a backend is disabled the Server will now start but the replication will be disabled
and and error will be logged :

[16/Mar/2009:10:39:31 +0100] category=SYNC severity=SEVERE_ERROR msgID=14942362 msg=The Replication was not started on base-dn cn=dc=example\,dc=com (domain 25795),cn=domains,cn=Multimaster Synchronization,cn=Synchronization Providers,cn=config : An unexpected error occurred when looking for the replicated backend : dc=example,dc=com. It may be not configured or disabled


The server will need to be restarted in order to enable replication on this base-dn