Strange problem !We also have Sarge based application servers, but I cannot reproduce your bug, only one connection is opened to the ldap server.
Our server was installed from scratch. My configuration file is similar but with debug and logfile disabled.
Cheers, -- Ludovic DROLEZ Linbox / Free&ALter Soft www.linbox.com lrs.linbox.org tel: +33 3 87 50 87 90 152 rue de Grigy - Technopole Metz 2000 57070 METZ