New XMLNS for JSTL tags not recognized (http://xmlns.jcp.org/jsp/jstl/core)

Although there are other (closed) issues relating to WildFly and the new http://xmlns.jcp.org namespaces, they still don't seem to work for JSTL?

Trying to use http://xmlns.jcp.org/jsp/jstl/core gives an error, whereas using the old http://java.sun.com/jsp/jstl/core works okay.

I am basing my understanding off this page: http://jsflive.wordpress.com/2013/05/16/jsf22-namespaces/