session处理机制
http://blog.tianya.cn/blogger/post_read.asp?BlogID=3290278&PostID=30831577


PHP将session存入数据库 
http://blog.chinaunix.net/uid-18962755-id-2808297.html


http://www.php100.com/html/webkaifa/PHP/PHPyingyong/2010/0226/4002.html


php实现SESSION跨域
http://blog.csdn.net/czloveyeer/article/details/6926430