diff --git a/projects/cadcAccessControl-Server/src/ca/nrc/cadc/ac/server/ldap/LdapDAO.java b/projects/cadcAccessControl-Server/src/ca/nrc/cadc/ac/server/ldap/LdapDAO.java
index 37c075396407ecfccd101aa63af2b82cbd158ab3..6d27de542a8dbbe0f5a067ea1356fe38d6e132c8 100755
--- a/projects/cadcAccessControl-Server/src/ca/nrc/cadc/ac/server/ldap/LdapDAO.java
+++ b/projects/cadcAccessControl-Server/src/ca/nrc/cadc/ac/server/ldap/LdapDAO.java
@@ -208,7 +208,8 @@ public abstract class LdapDAO
 
             SearchResult searchResult =
                     getConnection().search(config.getUsersDN(), SearchScope.ONE,
-                                           ldapField, "entrydn");
+                            "(&(objectclass=cadcaccount)" + ldapField + ")", 
+                            "entrydn");
 
             if (searchResult.getEntryCount() < 1)
             {