Name: gateway-mail/gateway.xml 
1:
<description datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes" xmlns="http://riddl.org/ns/description/1.0" xmlns:xi="http://www.w3.org/2001/XInclude">
2:
 
3:
  <message name="gateway-request">
4:
    <parameter name="gatewayRequest" mimetype="text/xml" handler="http://riddl.org/ns/handlers/relaxng">
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      <xi:include href="rngs/request.rng"/>
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    </parameter>
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  </message>
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9:
  <resource>
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    <post in="gateway-request"/>
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  </resource>
12:
   
13:
</description>