Assertion: Schema Compliance problem on WADL

Hi,

I'm trying to make a schema compliance assertion on a WADL, and particulary on a REST service response.
My service answers a "HTTP 204 No content" response which is valid against my WADL, but the assertion is still in error.

Here is a part of my WADL:

<method name="POST" id="enregistrerDonnees">
    <doc title="headerIn1">XXXXXXXXX</doc>
    <doc title="headerIn2">XXXXXXXXX</doc>
    <doc title="headerIn3">XXXXXXXXX</doc>
    <request>
     <param name="headerIn1" type="ihd:type_msisdn10" style="query" required="false" />
     <param name="headerIn2" type="ihd:type_email" style="query" required="false" />
     <param name="headerIn3" type="ihd:type_msisdn_avec_indicatif_sans_plus" style="header" required="true" />
    </request>
    <response>
     <representation status="204"/> 
    </response> 
    <response> 
     <representation status="200" mediaType="application/xml" element="ihd:EnregistrerDonneesQualifFaiErrOut"/>
    </response>     
   </method>

and here is the service's response which should be valid.

HTTP/1.1 204 No Content
Date: Mon, 20 Dec 2010 14:07:24 GMT
Server: Apache/2.0.63 (Unix)
Content-Length: 0
Set-Cookie: JSESSIONID=h1YqNPjGn84rqyjpmCmPvqZCpNrwFGDQFwp1xMBhG2Q2hkJh03zn!1525331465; path=/
X-Powered-By: Servlet/2.4 JSP/2.0
Content-Type: text/html

I'm using Soapui 3.5 Build dist-87-2010-03-01, Build Date 2010/03/01 17:27.

Thx.

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