I got the same thing.. but I figured out the mistake that I used perform( ) instead of execute( ) method. After replacing it with execute ( ) method, I got the output. There is one more thing.. If you use ActionErrors validate ( ) method, then you have to set the validate attribute to "true" right ? ok.. still you have nothing to validate. ok.. leave it.
You can refer to the url : http://www.theserverside.com/tt/articles/article.tss?l=StrutsActionMapping which indicates the ways of mapping for a better output.