[Plugin: W3 Total Cache] Any chance you could specify W3 total cache to don't touch a specific

Any chance you could specify W3 total cache to don’t touch a specific directory? We have some issue with some zip download files with our WP-ecommerce plugin. When someone purchase a zip digital file when W3 total cache is activated the zip file size is reduced.

http://wordpress.org/extend/plugins/w3-total-cache/