Topic: LDAP Address Book

Dear...one question..i would like to go with ldap backend in iredmail...

My users will send via thunderbird and lot's of address stored on local thunderbird database..i want to integrated with ldap server. Question are:

1. Ldap server will store all thunderbird addresses?
2. My users share addresses with each other without share mail id's
3. Can users add address direct on ldap server for share..