Ticket #609 - nsDS5BeginReplicaRefresh attribute accepts any value and it doesn't throw any error when server restarts.
    
    Bug description: If an invalid value is set to ds5BeginReplicaRefresh
    in an agreement, it does not affect the behaviour, but it does not get
    purged from the agreement and causes an error if "ds5BeginReplicaRefresh:
    start" is added.
    
    Fix description: Adding an invalid ds5BeginReplicaRefresh is rejected
    with "DSA is unwilling to perform" and the following error is returned:
        ldap_modify: additional info: Invalid value (junk_value123) value
    	supplied for attr (nsds5BeginReplicaRefresh); Ignoring ...
    
    Reviewed by Rich (Thank you!!)
    
    https://fedorahosted.org/389/ticket/609