help:about jboss access http://localhost:8080/

I install jboss-3.0.4_tomcat-4.1.12 to deploy my app.

after startup jboss+tomcat,I try test some script,so i put it in tomcat'directory: myapp\Root\, but I can't access,error:
=============================================
HTTP Status 500 - No Context configured to process this request
=============================================

I already modify tomcat'server.xml:
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<!-- Tomcat Root Context -->

<Context path="/" docBase="ROOT" debug="0"/>
==============================================

and I can't standalone start tomcat,but JBOSS+Tomcat do.

why?

thanks in advance.
best regards.

//flowerpp