JSTL: Tag Library Validator -- PermittedTaglibs Error

<%@ taglib prefix="permittedTaglibs" uri="http://jakarta.apache.org/taglibs/standard/permittedTaglibs" %> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ taglib prefix="ex" uri="/jstl-examples-taglib" %> JSTL: Tag Library Validator -- PermittedTaglibs Error

This JSP page uses taglibs that are not permitted. A translation error will occur.

Using custom tags <even> and <odd>