[Opensymphony-oscache] Using CacheFilter to set Expires Headers

Hello all,

I've added the CacheFilter to my site (http://raibledesigns.com) to
try and set expires headers on my images. However, it doesn't seem to
be working. Any ideas?

Here's my configuration in web.xml:

    <filter>
        <filter-name>CacheFilter</filter-name>
        <filter-class>com.opensymphony.oscache.web.filter.CacheFilter</filter-class>
        <init-param>
            <param-name>expires</param-name>
            <param-value>time</param-value>
        </init-param>
        <init-param>
            <param-name>time</param-name>
            <param-value>2592000</param-value> <!-- one month -->
        </init-param>
        <init-param>
            <param-name>scope</param-name>
            <param-value>session</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>CacheFilter</filter-name>
        <url-pattern>*.gif</url-pattern>
    </filter-mapping>
    <filter-mapping>
        <filter-name>CacheFilter</filter-name>
        <url-pattern>*.jpg</url-pattern>
    </filter-mapping>
    <filter-mapping>
        <filter-name>CacheFilter</filter-name>
        <url-pattern>*.png</url-pattern>
    </filter-mapping>

Thanks,

Matt