xfire开发的webservice应用部署出错

在Weblogic11部署xfire开发的webservice应用，部署成功后，在IE访问wsdl接口地址，出现以下错误：
shengzlkv2Log:2011-05-10 11:16:18 ERROR: org.codehaus.xfire.transport.http.XFireServletController#doService : Couldn't invoke servlet request.
java.lang.ClassCastException: weblogic.xml.jaxp.RegistrySAXTransformerFactory
at javax.xml.transform.TransformerFactory.newInstance(Unknown Source)
at org.codehaus.xfire.wsdl11.builder.SchemaSerializer.writeXml(SchemaSerializer.java:46)
at org.codehaus.xfire.wsdl11.builder.SchemaSerializer.marshall(SchemaSerializer.java:35)
at com.ibm.wsdl.xml.WSDLWriterImpl.printExtensibilityElements(Unknown Source)
at com.ibm.wsdl.xml.WSDLWriterImpl.printTypes(Unknown Source)
at com.ibm.wsdl.xml.WSDLWriterImpl.printDefinition(Unknown Source)
at com.ibm.wsdl.xml.WSDLWriterImpl.writeWSDL(Unknown Source)
at com.ibm.wsdl.xml.WSDLWriterImpl.writeWSDL(Unknown Source)
at org.codehaus.xfire.wsdl11.builder.WSDLBuilder.write(WSDLBuilder.java:182)
at org.codehaus.xfire.wsdl11.builder.WSDLBuilderAdapter.write(WSDLBuilderAdapter.java:40)
at org.codehaus.xfire.DefaultXFire.generateWSDL(DefaultXFire.java:104)
at org.codehaus.xfire.transport.http.XFireServletController.generateWSDL(XFireServletController.java:380)
at org.codehaus.xfire.transport.http.XFireServletController.doService(XFireServletController.java:125)
at org.codehaus.xfire.transport.http.XFireServlet.doGet(XFireServlet.java:108)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:821)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:300)
at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:27)
at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:57)
at com.opensymphony.sitemesh.webapp.SiteMeshFilter.obtainContent(SiteMeshFilter.java:136)
at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:77)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3650)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2174)
at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1446)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:173)
<2011-5-10 上午11时16分18秒 CST> <Error> <HTTP> <BEA-101017> <[ServletContext@266783129[app:dataExchange_test module:dataExchange_test path: spec-version:null]] Root cause of ServletException.
java.lang.ClassCastException: weblogic.xml.jaxp.RegistrySAXTransformerFactory
at javax.xml.transform.TransformerFactory.newInstance(Unknown Source)
at org.codehaus.xfire.wsdl11.builder.SchemaSerializer.writeXml(SchemaSerializer.java:46)
at org.codehaus.xfire.wsdl11.builder.SchemaSerializer.marshall(SchemaSerializer.java:35)
at com.ibm.wsdl.xml.WSDLWriterImpl.printExtensibilityElements(Unknown Source)
at com.ibm.wsdl.xml.WSDLWriterImpl.printTypes(Unknown Source)
Truncated. see log file for complete stacktrace
>  请问各位高手，java.lang.ClassCastException: weblogic.xml.jaxp.RegistrySAXTransformerFactory，是什么错误，如何解决？