I'm new to richfaces development and am starting with a very basic app, I wanted to test some a4j functionality but am getting the following error when trying to view my page:

javax.faces.view.facelets.TagException: /index.xhtml @14,16 <a4j:form> Tag Library supports namespace: http://richfaces.org/a4j, but no tag was defined for name: form


Despite a day of messing around with web.xml configuration and adding/subtracting jars from my war I can't seem to figure out why I'm getting this error.  Can anyone help me understand what is going on?

my web.xml looks like:

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"

    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="

      http://java.sun.com/xml/ns/javaee

      http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">

    <!-- This is an optional parameter, but it makes troubleshooting errors

        much easier -->

    <!-- You should remove this context parameter before deploying to production! -->

    <context-param>

        <param-name>javax.faces.PROJECT_STAGE</param-name>

        <param-value>Development</param-value>

    </context-param>

    <context-param>

        <param-name>org.apache.myfaces.annotation.SCAN_PACKAGES</param-name>

        <param-value>com.mypackage</param-value>

    </context-param>

    <context-param>

        <param-name>org.richfaces.SKIN</param-name>

        <param-value>blueSky</param-value>

    </context-param>

    <context-param>

        <param-name>org.richfaces.CONTROL_SKINNING</param-name>

        <param-value>enable</param-value>

    </context-param>

    <filter>

        <display-name>RichFaces Filter</display-name>

        <filter-name>richfaces</filter-name>

        <filter-class>org.ajax4jsf.Filter</filter-class>

    </filter>

    <filter-mapping>

        <filter-name>richfaces</filter-name>

        <servlet-name>Faces Servlet</servlet-name>

        <dispatcher>REQUEST</dispatcher>

        <dispatcher>FORWARD</dispatcher>

        <dispatcher>INCLUDE</dispatcher>

    </filter-mapping>

    <!-- Activate the JSF 2.0 servlet -->

    <servlet>

        <servlet-name>Faces Servlet</servlet-name>

        <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>

        <load-on-startup>1</load-on-startup>

    </servlet>

    <!-- Tell the context which URLs to process with JSF -->

    <servlet-mapping>

        <servlet-name>Faces Servlet</servlet-name>

        <url-pattern>*.xhtml</url-pattern>

    </servlet-mapping>

    <!-- This section is optional. We are allowing index.jsf to handle the root

        URL (i.e., /). -->

    <welcome-file-list>

        <!-- Add additional files here, if desired, for example: <welcome-file>index.html</welcome-file> -->

        <welcome-file>index.xhtml</welcome-file>

    </welcome-file-list>

</web-app>