Address Book results using LDAP

I'm using Outlook 2007 with an LDAP address book. When we click on the
address book button, the address book comes up and displays all of our users
with mail accounts (we use a Check Names filter of mail=*). However, it
doesn't display any groups that have an email address unless we select More
Columns and enter any sort of search criteria, but ideally I'd like the
groups to be listed with the users when we do the Name only search since that
option brings up the list without any user input. Is this possible?

I've also tried using a Check Names filter of
(|(&(ObjectClasss=User)(mail=*))(objectclass=groups)(mail=*))) with the same
result.