WSDL message part from a no namespace schema

Is it possible to create a WSDL with message parts that refer to an
in-line schema with no targetNamespace ?

I have created one of these and whilst by XML editor doesn't complain,
if I run the WS-I BP 1.1 profile checking tool it fails the compliance
test. Here is an example of what I mean :-

<wsdl:definitions xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
targetNamespace="urn:testNonamespaceMsgPart">
    <wsdl:types>
        <xs:schema>
            <xs:element name="Root">
                <xs:complexType>
                    <xs:sequence>
                        <xs:any processContents="skip" namespace="##any"/>
                    </xs:sequence>
                </xs:complexType>
            </xs:element>
        </xs:schema>
    </wsdl:types>
    <wsdl:message name="msgRequest">
        <wsdl:part name="Rq" element="Root"/>
    </wsdl:message>
	...

</wsdl:definitions>