Thunderbird + Exchange

Тоже пробовал... эффект тот же
Тут видимо какой-то косяк с DN как их правильно записать...

Вот такой ответ помог :)
http://kb.mozillazine.org/LDAP_access_via_Address_Book

Connecting to an Active Directory (AD) on a MS Small Business Server

"General" tab:

    * Name: Choose a name for this server (there is no must-have value for the field "name"; just choose something).
    * Hostname: The IP address of the server or a domain name which can be resolved from the computer Thunderbird is running on. Keep in mind that there shoud be no firewall blocking the requests.
    * Base DN: When connecting from Thunderbird to an SBS Server, this sould be something like: "ou=SBSUsers,ou=Users,ou=MyBusiness,dc=NameOfMyDomain,dc=local".
    * Port number: Should be 636 when connecting to the server via a non-secure or non-private network; otherwise you can use 389. (Keep firewalls in mind which might block your port requests.)
    * Bind DN: When connecting to an AD on an SBS environment use: "myLoginUsername@NameOfMyDomain.local".
    * Use secure connection (SSL): Checking the SSL option should be the prefered way of operation when connection via public or non-secured networks. Also keep the port setting in mind when changing this. 

"Offline" tab:

No changes needed if you want to connect to an AD on an SBS System.

"Advanced" tab:

Choose whatever you like at this tab, but good values should be:

    * Don't return more than ___ results: 100
    * Scope: Subtree
    * Search filter: "(objectclass=*)"