We have BlackBerry enterprise servers connecting to Exchange mailboxes
in a Microsoft HMC environment. Users in a HMC platform have the CN in
the format dnoakes@domain.com where the description/display name/
mailbox name is Daniel Noakes.
To support multiple GAL's we have added entries in to the registry
(see below) as specified in the BES 4.1.4 Administration Guide in the
section titled, Configuring address lookup support in a hosted
environment. This is working as expected, only returning results for
users with a matching extensionAttribute1.

HKEY_LOCAL_MACHINE\Software\Research In Motion\BlackBerry Enterprise
Server\Agents
"HostedServer"=dword:00000001
"LDAPSearch"=dword:00000001
"LDAPALPSearch"=dword:00000001
"LDAPCompanyField"="extensionAttribute1"

If I perform a GAL lookup from a BlackBerry handheld for Daniel the
dnoakes@domain.com user will not be listed, if I search for dnoakes it
is. As you can imagine this is causing some confusion for end users,
and re-education of users from different organisations spread across
this world is not really an option.
I need to know if it is possible to change the attribute that the name
is resolved to from the CN to another attribute such as, Description
or Display Name. I have looked in the registry and BES files for
possible clues, but have not been successful.

Archived from group: microsoft>public>exchange>mobility