Scripting

I've taken down the Orgs feature in 6.3 and I have all my users logging in to the default org. Now I'd like to set up LDAP labels to sort the users into three groups. There isn't anything identifiable in their profiles in AD so I'm using the company field and assigning Alpha, Beta, Charlie. Then I have a fourth group that is all encompassing and should have every user. The way I'm doing this is using my domain in the Search Base DN and this in the Search Filter.

(&(objectcategory=Person)(company=ALPHA)) 

When I run these in the LDAP Browser to test them I get the exact results I want every time. What is happening is all four groups are being populated with every user. It is ignoring my filter using company. Is there another field that I can use that would give me better results? Is there a way to modify this one to make it efficient?

Once I have this one down then I need to do something similar for all of their computers. Thanks for the help.