LDAP "Insufficient Access"

Question

I am trying to create an LDAP filter string. In each LDAP entry there is an attribute called "status" that has many values, some of which are of the regex form "[ab][0-9][1-9]". For example, "a20" or "b81". All other values for the "status" attribute are just alphabetical characters.

I only want to let through entries that have a "status" value of the first form. When I construct an LDAP filter such as

(status=a*)

I get an "Insufficient Access" error. However, if I change the query to

(status=a1*)

that works fine. Is there any reason for this? If there behavior is unavoidable, can anyone thing of a way to get only the entries I want.