Cisco CUCM or Unity Connection LDAP filter

Filter LDAP record import by whether MS AD ipPhone field is populated:

This will work:
(ipPhone=*)

This will work as well, and includes the default search criteria (go with this):
(&(objectclass=user)(!(objectclass=Computer))(!(UserAccountControl:1.2.840.113556.1.4.803:=2))(ipPhone=*))

In case your really lost, put it here: