Pfsense URL-based firewall rules?

[feait]

We are having issues firewalling all internet access except some required sites - most sites use a limited range of IP addresses so outbound LAN->WAN firewall rules are easy.  Google Earth however, which is required for business purposes, uses a large number of regularly changing IP addresses - making firewall rules based on IP address/port useless.
Is there a way of getting pfSense 1.2.2 to do a firewall pass rule based on the URL (eg http://maps.google.com) as there are 4 URL's required for google earth access.

Regards,
Greg Hastings
Systems Administrator
FEA Ltd

[ktims]

Install Squid and SquidGuard packages and enable transparent proxying. Then add . in your blocklist and allow the sites you need.