JSTL Error

Problem:
Compile error from tomcat when it encounters a JSP: "According to TLD or attribute directive in tag file, attribute value does not accept any expressions"

Solution:
For some reason the JSP is using the 1.2 JSP (and 1.0 JSTL) and EL expressions aren't understood. There's a lot of hits on the web for this but in summary there are 2 important things to do to ensure you're getting the right version of the spec:

1. Reference the correct servlet specification in your deployment descriptor:

   
   
   xmlns="http://java.sun.com/xml/ns/j2ee"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">

   
   
2. Reference the correct JSTL uri in your JSP:
   change

   
   <%@ taglib uri='http://java.sun.com/jstl/core' prefix='c'%>

   
   to

   
   <%@ taglib uri='http://java.sun.com/jsp/jstl/core' prefix='c'%>

Notes:

What Specification goes with what?
Web-app(deployment schema)	2.3	2.4	2.5
	http://java.sun.com/dtd/web-app_2_3.dtd	http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd
Servlet	2.3	2.4	2.5
JSP	1.2	2.0	2.1
JSTL(core uri reference)	1.0	1.1	1.2
	http://java.sun.com/jstl/core	http://java.sun.com/jsp/jstl/core	http://java.sun.com/jsp/jstl/core
Tomcat	4.x	5.x	6.x
WebSphere	5.x	6.x	7.x (?)