Dropbox Wiki on "[Plugin: W3 Total Cache] W3TC CDN SSL Auto Not Working"

It seems that the Auto selection is not working when an https page is loaded. Since I'm using CloudFlare, I've set the rule in my wp-config.php with

if ($_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https')
$_SERVER['HTTPS']='on';

However, it doesn't seem to have W3TC see that it is an https page, so it still uses the http version from MaxCDN. I have the URLs in the replace site url hostname with

cdn.dropboxwiki.com,dropboxwiki-dropboxwiki.netdna-ssl.com

so the first should be for http pages and the second for https pages. The interesting thing is that pages that I explicitly state are to be https using WordPress HTTPS work with the ssl version of my MaxCDN url being used.

How does W3TC determine that a page is ssl? And is there anything more I need to implement to get this to work?

Thanks!

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