OWASP CSRFGuard not working (404 not found error)

Question

I am trying to protect my web application using OWASP CSRFGuard. Below are the required configuration files

web.xml

<servlet>
    <servlet-name>CsrfServlet</servlet-name>
    <servlet-class>org.owasp.csrfguard.servlet.JavaScriptServlet</servlet-class>
    <init-param>
        <param-name>source-file</param-name>
        <param-value>WEB-INF/csrfguard.js</param-value>
    </init-param>
    <init-param>
        <param-name>inject-into-forms</param-name>
        <param-value>true</param-value>
    </init-param>
    <init-param>
        <param-name>inject-into-attributes</param-name>
        <param-value>true</param-value>
    </init-param>
    <init-param>
        <param-name>domain-strict</param-name>
        <param-value>false</param-value>
    </init-param>
    <init-param>
        <param-name>referer-pattern</param-name>
        <param-value>.*</param-value>
    </init-param>
</servlet>
<servlet-mapping>
    <servlet-name>CsrfServlet</servlet-name>
    <url-pattern>/csrfguard</url-pattern>
</servlet-mapping>

I have placed the required csrfguard.js and csrfguard.properties in web/WEB-INF/ directory (without any modification). I have also placed the following line in one test jsp page

<script src="/csrfguard"></script>

But whenever the page is loaded the browser gives a 404 error while loading csrfguard.

I am not sure what I am doing wrong here. Some help would be appreciated.