open_basedir issue vhost.conf

[streetconcepts]

I was wondering if anyone knows how i can add multiple open_basedir scripts within a single vhost.conf file.

Basically i'm trying to get sitea.com to view and edit files on siteb.com

i.e. /home/httpd/vhosts/siteb.com/httpdocs/foldername

however i currrently have a php_admin_value open_basedir set within my vhost.conf file and i would like to add another one.

Any ideas?