class object_lock_table :string list -> string -> string -> string ->object..end
new object_lock_table ldapurls binddn bindpw mutexdn
method lock : Ldap_types.dn -> unitlock the specified dn, if it is already locked, then block until the lock can be aquired
method unlock : Ldap_types.dn -> unitunlock the specified dn, if it is not locked do nothing