How to echo the classpathref?

For debugging purpose I want to echo the actual classpathref. But it does not work by using something like this:

    <path id="all.you.can.need.class.path">
        <fileset dir="${eclipse-home}/plugins">
            <include name="**/*.jar"/>
        </fileset>
    </path>
   
    <target name="echo">
        <echo>${all.you.can.need.class.path}</echo>
    </target>

It prints nothing although there are jars in this dir.

Any idea how to echo it?