For more information about designing a secure directory, see the following resources:
Sun Developer Security Resources http://developers.sun.com/techtopics/security/index.html
Understanding and Deploying LDAP Directory Services. T. Howes, M. Smith, G. Good, Macmillan Technical Publishing, 1999
SecurityFocus.com http://www.securityfocus.com/
Computer Emergency Response Team (CERT) Coordination Center http://www.cert.org/
CERT Security Improvement Modules http://www.cert.org/security-improvement/