You'll want to use port 3268 to talk to AD instead of the standard LDAP port 389; some of the links from the above will explain why.
From: "Krishnamoorthi Gopal" <firstname.lastname@example.org>
Sent: Thursday, March 7, 2013 11:58:56 AM
Subject: SvnServe with Windows AD Authendication
Is possible to integrate svnserve subversion ( SVN://) with Windows 2003 Active Directory for authentication?
Could you please confirm.
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