When I try to use an optional task such as junit, I get a "taskdef not found" 
message from ant.  I have tried putting ant-optional.jar in my netbeans/lib/ext 
director.  This task works when I use it outside of netbeans, so it appears 
that this is a classpath error of some sort.  I even tried explicitly adding a 
taskdef element to my build.xml file with a classpath defined and it still 
didn't work.