Please review the following fix for ticket #504
If schema modification is disabled, the access to the attribute syntax
table can be done without locking.
In that state a client attempt to modify the scema needs to be rejected.
https://fedorahosted.org/389/ticket/504
https://fedorahosted.org/389/attachment/ticket/504/0001-Fix-for-ticket-50...
Regards,
Ludwig