javax.servlet.ServletException: java.lang.NoSuchMethodError: javax.el.ExpressionFactory.newInstance()Ljavax/el/ExpressionFactory

This happens because we had a wlfullclient.jar with javax.el package different from the one in JSTL libraries..... the only solution was to remove that package from wlfullclient.jar

What a pain.... modules in Java ... 8? or 7 already? should take care of this problem