AD GAL Accounts without Email Address

[jeremywatco]

Hi All,
I have our GAL configured as an ExternalGAL pulling from Active Directory. On the web client everything looks great. On any client with the Outlook Connector or Zimbra Desktop the GAL contains a list of EVERY user and group in the directory regardless if it has an email address attached.
Any idea how to filter it so that only users with email addresses get added to the GAL?
zmprov gcf zimbraGalLdapFilterDef | grep ad: -- Yields this:
zmprov gcf zimbraGalLdapFilterDef | grep ad:

zimbraGalLdapFilterDef: ad:(&(|(displayName=*%s*)(cn=*%s*)(sn=*%s*)(givenName=*%s*)(mail=*%s*))(!(msExchHideFromAddressLists=TRUE))(|(&(objectCategory=person)(objectClass=user)(!(homeMDB=*))(!(msExchHomeServerName=*)))(&(objectCategory=person)(objectClass=user)(|(homeMDB=*)(msExchHomeServerName=*)))(&(objectCategory=person)(objectClass=contact))(objectCategory=group)(objectCategory=publicFolder)(objectCategory=msExchDynamicDistributionList)))