Scan not detecting new exploit

It looks like Wordfence scan is not detecting the (new) type of exploit code described here: http://blog.sucuri.net/2014/10/wordpress-websites-continue-to-get-hacked-via-mailpoet-plugin-vulnerability.html

I’ve just been doing a major clean of a server with a number of plugin and theme files (as well as core) with this type of code at the top; I can provide a full example as needed, but Wordfence detected no problems with the site even after I manually confirmed this exploit code was in place.

https://wordpress.org/plugins/wordfence/