Ah … we haven't ourselves tested that … we should though.
To preview PHP-driven pages currently (unless you can get Quercus to work before we look into), you can mount your web project via CIFS and then set up your preview environment against that mountpath. You'll bypass the virt server, of course, in this process, but that's OK because currently it's designed to virtualize Java web apps. Non Java web apps best tested via CIFS.
Kevin