The first time I tried to push data into AD with Net:LDAP I found out that it

• has a hardlimit of 1000 returned entries and needs paging, e.g. with Net::LDAP::Control::Paged (I also guess that might be your problem)
• doesn't use utf8 for saving data (or at least the admintools can't work with utf8), and Net::LDAP v3 automatically uses utf8 with gives problems with non-ascii-chars (e.g. german umlauts). I could solve this problem with using Net::LDAP with LDAPv2.
• I found no way to query the Global Catalog with Net::LDAP (well, I didn't search too hard)

So I turned over to ADSI with pure Win32::OLE which is also easier because there exists more documentation with good examples. Disadvantage: it only runs under Win32.

Useful links for ADSI:

• http://rallenhome.com/books/adcookbook/code.html
• http://www.perl.com/pub/a/2001/12/19/xmlrpc.html
• http://isg.ee.ethz.ch/tools/realmen/det/adsi.en.html
• Perlmonks -> ActiveDirectory
• Perlmonks -> ADSI