dict: ldap deref

Hello,

just been testing sieve extlists against ldap dict in 2.4.5 -- works ok but need to narrow a search base but this would require setting deref other than default none for the ldap client. Seems that something like ldap_deref = always in dict_map {} section does not work (is not even documented, but config is parsed ok on the other hand) and value of the global ldap_deref is not picked up either. Question is whether the deref parameter is supposed to work and if yes, where to set it up correctly...

Many thanks, Tomas