Using Apache's proxy module for specific file types

Hello everyone, I was reading the article found at: http://www.linux.com/articles/51673 (great read btw, very helpful) And a question came to mind. How would I go about specifying specific file types to go through lighttpd in the httpd.conf file? The code mentioned in the article is: [code]ProxyRequests Off ProxyPreserveHost On ProxyPass /images http://0.0.0.0:81/ ProxyPassReverse / http://0.0.0.0:81/ [/code] But I'd like to use a conditional statement to specify that all images with an extension of mp3, gif, jpg, bmp, png, etc, etc (any media) instead of simply those within the images folder. Unfortunately, I'm unaware if it's even possible to use some sort of condition in an httpd.conf file. (I'm thinking almost along the lines of what is possible in an .htaccess file) If this is infact not possible, would anyone have any suggestions for an alternative? Thank you for your time, Daniel St. Jules