ldap queries to AD server

Hello,

I am seeing a large amount of queries for users such as vpopmail, postmaster, anonymous and a few other users being sent to the AD server via the openldap proxy. Below is a snippet of the log, I was curious how I could stop the servers from searching for these users via ldap?

[ snippet ]

Oct 28 14:32:54 ldap-proxy slapd[21165]: conn=2828 op=56 SRCH base="ou=Internal,dc=mgmt,dc=test,dc=net" scope=2 deref=0 filter="(&(objectClass=shadowAccount)(uid=vpopmail))"

Oct 28 14:32:54 ldap-proxy slapd[21165]: conn=2828 op=56 SRCH attr=uid userPassword shadowLastChange shadowMax shadowMin shadowWarning shadowInactive shadowExpire shadowFlag

[ end snippet ]