Re: Error on my xml descriptor when deploying a war file in 2.1

I think the descriptor you are using is out of date. We no longer
specify the configId and parentId in the <webapp> element. You can use
 this sample application as a reference:
http://cwiki.apache.org/GMOxDOC21/web-application-security-sample.html.

The key is

        <environment>
                <moduleId>
                        <groupId>org.apache.geronimo.samples</groupId>
                        <artifactId>timereport-war</artifactId>
                        <version>2.1</version>
                        <type>war</type>
                </moduleId>
        </environment>

Thanks,
Viet