prefs for LDAP filters in addressbook window

Hello,

When I search someone in a directory, the LDAP query return all
entries whose
names (cn) or mail contains the word I typed.

I could of course narrow my query, using "advanced" button.

I want to be able to customize the default query (for example
retrieving entries
whose "cn" begins with what I typed).

My request doesn't apply to autocomplete filter template :
ldap_2.servers.mydirectory.autoComplete.filterTemplate


I found this pref : "mail.addr_book.quicksearchquery.format"
But the query format seems to apply to every directory server.
We have three directories and I would like to specify different query
fiters for each directory.
Do you have some knowledge about this ?


Thank you.