Why can't I get to the depend task?

[Peter Vogel]

<project name="foo" basedir="..">    
    <taskdef name="depend"
classname="org/apache/tools/ant/taskdefs/optional/depend/Depend.class">
        <classpath>
            <pathelement location="c:/ant-new/lib/optional.jar">
        </classpath>
    </taskdef>

    ...

</project>

I have optional.jar in the location specified, it has Depend.class, etc, but
I get
a ClassNotFound exception...

Thanks,
-Peter

--
Peter A. Vogel
Manager+consultant, Configuration Management
Arsin Corporation, Professional Services
http://www.arsin.com