soap response does not respect minOccurs=0

$ ant -Dtest=org.jboss.test.webservice.jbws168.JBWS168TestCase one-test

<env:Envelope xmlns:env='http://schemas.xmlsoap.org/soap/envelope/'>
<env:Header/>
<env:Body>
<ns1:hello xmlns:ns1='http://org.jboss.test.webservice/jbws168/types' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'>
<UserType_1>
<propC/>
<propA>A</propA>
</UserType_1>
</ns1:hello>
</env:Body>
</env:Envelope>
2005-06-23 01:00:02,531 DEBUG [org.jboss.ws.handler.HandlerChainBaseImpl] Enter: doHandleRequest
2005-06-23 01:00:02,531 DEBUG [org.jboss.ws.handler.HandlerChainBaseImpl] Handle request: [state=METHOD_READY,handler=org.jboss.test.webservice.jbws168.HelloHandler@1bcf3d]
2005-06-23 01:00:02,531 INFO [org.jboss.test.webservice.jbws168.HelloHandler] handleRequest
2005-06-23 01:00:02,581 INFO [STDOUT] <env:Envelope xmlns:env='http://schemas.xmlsoap.org/soap/envelope/'><env:Header/><env:Body><ns1:hello xmlns:ns1='http://org.jboss.test.webservice/jbws168/types' xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'><UserType_1><propC/><propA>A</propA></UserType_1></ns1:hello></env:Body></env:Envelope>
2005-06-23 01:00:02,581 ERROR [org.jboss.test.webservice.jbws168.HelloHandler] Handler processing error
java.lang.RuntimeException: Cannot find attribute xsi:nil
at org.jboss.test.webservice.jbws168.HelloHandler.validateMessageContent(HelloHandler.java:146)
at org.jboss.test.webservice.jbws168.HelloHandler.handleRequest(HelloHandler.java:82)