When you search Active Directory you have the option of asking the server to return search statistics for your query. This is done by adding an LDAP control to your query. The control is 1.2.840.1135188.8.131.520. I was using LDP to test this out on my test forest. The forest runs Windows Server 2003 DCs and I use the W2K3 version of the Active Directory Administration Tool; LDP. In that version of LDP it is very easy to add the required LDAP control to the search, you just select it from a drop-down box from the Search Controls dialog.
I specifically wanted to see the expanded queries that the server extrapolates when using ANR searches, or LDAP Display Names in objectCategory searches. But to my surprise, the server never returned any statistics. I always got the same standard output; the result of my search and nothing more. After a little investigation I found the following text on the MSDN site:
To retrieve all of the above information [search statistics], the account that issues the LDAP request should have debug privileges in its token.
I remembered having tested PWDUMP on that particular server. PWDUMP requires the debug privilege to work. I had removed that from the Administrators group to test something with PWDUMP. When I gave it back and logged off and on again i could successfully see the search statistics from the domain controller.