safe mode/open basedir not working ?

Hi, I host a few virtual domains in apache 2 and use php. The virtual domain is something like <VirtualHost a.b.c.d:80> ServerAdmin webmaster@domain.com DocumentRoot /home/httpd/html/domain.com ServerName www.domain.com ErrorLog logs/domain.com-error_log CustomLog logs/domain.com-access_log combined ScriptAlias /cgi-bin/ /home/httpd/cgi-bin/ <Directory /home/httpd/html/domain.com/> AllowOverride AuthConfig Limit php_admin_value doc_root "/home/httpd/html/domain.com/" php_admin_flag safe_mode on php_admin_value open_basedir "/home/httpd/html/domain.com:/tmp/" </Directory> </VirtualHost> Recently I had a minor problem with a user that uploaded via ftp a php script in his domain and this domain used exec/system etc to call perl, read files. Shouldn't the settings above retrict such thing ?