Net::LDAP::Gateway contains a sample LDAP server that can dump the packets it receives as almost-human-friendly Perl data structures. It has served me in the past to compare and validate requests made through Net::LDAP and ldapsearch and solve problems as the one you were facing.
Snippets of code should be wrapped in
<code> tags not<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor