Metro webservices on tomcat: ClassCastException

If you get the following error message

com.sun.xml.ws.transport.http.servlet.WSServletContextListener contextInitialized
SEVERE: WSSERVLET11: failed to parse runtime descriptor: com.sun.xml.ws.util.ServiceConfigurationError: com.sun.xml.ws.api.wsdl.writer.WSDLGeneratorExtension: Provider com.sun.xml.ws.policy.jaxws.PolicyWSDLGeneratorExtension is specified in jar:file:/home/mla/apache-tomcat-5.5.27/shared/lib/webservices-rt.jar!/META-INF/services/com.sun.xml.ws.api.wsdl.writer.WSDLGeneratorExtensionbut could not be instantiated: java.lang.ClassCastException
com.sun.xml.ws.util.ServiceConfigurationError: com.sun.xml.ws.api.wsdl.writer.WSDLGeneratorExtension: Provider com.sun.xml.ws.policy.jaxws.PolicyWSDLGeneratorExtension is specified in jar:file:/home/mla/apache-tomcat-5.5.27/shared/lib/webservices-rt.jar!/META-INF/services/com.sun.xml.ws.api.wsdl.writer.WSDLGeneratorExtensionbut could not be instantiated: java.lang.ClassCastException

after installing metro 1.3.1 into tomcat using the metro_on_tomcat.xml ant buildfile two incompatible webservice implementations are installed.

he easy solution is to remove all files starting with "webservices" from the tomcat/shared/lib directory.