It's possible, and actually fairly simple. http://lmgtfy.com/?q=subversion+apache+ldap+3268+active+directory yields lots of good links.

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" <krishnamoorthi@vernal.is>
To: users@subversion.apache.org
Sent: Thursday, March 7, 2013 11:58:56 AM
Subject: SvnServe with Windows AD Authendication


Hi Team,

Is possible to integrate svnserve subversion ( SVN://) with Windows 2003  Active Directory for authentication?

Could you please confirm.

Regards
Support Team.

VERNALIS SYSTEMS EMAIL NOTICE
-----------------------------
The information contained in this email and any attachments is confidential and may be subject to copyright or other intellectual property protection. If you are not the intended recipient, you are not authorized to use or disclose this information, and we request that you notify us by reply mail or telephone and delete the original message from your mail system.