dynamic virtual hosting+open_basedir

Hi! I have a problem with my httpd.conf and PHP. I would like to make a free PHP hosting. When a user register, I put into directory /foo/bar/username.mydomain.com. My httpd.conf is the following: <Directory /foo/bar> AllowOverride None Options None php_admin_value max_execution_time 30 #The following line is my QUESTION !!! php_admin_value open_basedir . </Directory> <VirtualDocumentRoot aaa.bbb.ccc.ddd> VirtualDocumentRoot /foo/bar/%0 </VirtualHost> BUT if the user "foobar" (dir: /foo/bar/foobar.mydomain.com) have a directory name "include" (/foo/bar/foobar.mydomain.com/includes), he can't be able to reach the parent directory from includes, like include("../config.php"); becouse open_basedir restriction in affect. So I have to SET dynamicly open_basedir for every user. I have to simulate this line's, but dont't know how? user1: php_admin_value open_basedir "/foo/bar/user1.mydomain.com" user2: php_admin_value open_basedir "/foo/bar/user2.mydomain.com" . . . userN: php_admin_value open_basedir "/foo/bar/userN.mydomain.com"