要PHP可以连接到用self-signed certificate的ldaps服务器，需要在/etc/ldap.conf中添加一行：
TLS_REQCERT never
要PHP在Apache中连接到用self-signed certificate的ldaps服务器，需要在httpd.conf中添加一行：
LDAPVerifyServerCert Off
PHP, LDAPS and Apache
原文：http://www.cnblogs.com/amonw/p/4537407.html
