WCF MTOM Attachments, byte[] data is null

I'm facing with a situation when my MTOM enabled WCF service is trying to parse MTOM request coming from Java client .

Incoming MTOM request:

--uuid:36b9a19b-37bc-4d67-8319-d8a9dad74ac6
Content-Type: application/xop+xml; charset=UTF-8; type="application/soap+xml"; action="sendData";
Content-Transfer-Encoding: binary
Content-ID: rootContentID

<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope">
    <soap:Body>
        <nsX:dataRequest xmlns:xmime="http://www.w3.org/2005/05/xmlmime" xmlns:nsX="http://abc.com/XYZ">
            <param1>StringData1</param1>
            <binaryData xmime:contentType="application/octet-stream">
                <xop:Include xmlns:xop="http://www.w3.org/2004/08/xop/include" href="attachmentContentID"/>
            </binaryData>
            <param2>StringData2</param2>
        </ns3:dataRequest>
    </soap:Body>
</soap:Envelope>
 
--uuid:36b9a19b-37bc-4d67-8319-d8a9dad74ac6
Content-Type: application/octet-stream
Content-Transfer-Encoding: binary
Content-ID: attachmentContentID
 
---------------------------
----- binaryData    -------
---------------------------
 
--uuid:36b9a19b-37bc-4d67-8319-d8a9dad74ac6--

My service definition:

[ServiceContract(Namespace = "http://abc.com/XYZ")]
publicinterfaceIService1
{
    [OperationContract(Action = "*")]
    returnType sendData(sendType req);
}
 
 
[MessageContract(WrapperName = "dataRequest", WrapperNamespace = "http://abc.com/XYZ")]
publicclass sendType
{
    privatestring param1Field;
    privatebyte[] binaryDataField;
    privatestring param2Field;
 
    [MessageBodyMember(Namespace = "")]
    publicstring param1 { get { return param1Field; } set { param1Field = value; } }
 
    [MessageBodyMember(Namespace = "")]
    [System.Xml.Serialization.XmlTextAttribute(DataType = "base64Binary")]
    publicbyte[] binaryData { get { return binaryDataField; } set { binaryDataField = value; } }
 
    [MessageBodyMember(Namespace = "")]
    publicstring param2 { get { return param2Field; } set { param2Field = value; } }
}

Service implementation:

publicclassService1 : IService1
{
    public returnType sendData(sendType req)
    {
        // req.param1 = StringData1   OK
        // req.param2 = StringData2   OK
        // req.binaryData = null      ????
    }
}

And web.config definitions:

<system.serviceModel>
 
    <serviceHostingEnvironmentaspNetCompatibilityEnabled="true"/>
 
    <services>
      <servicename="WCFMTOM.Service1"behaviorConfiguration="ServiceBehavior">
        <endpointaddress="https://www.xyz.com/mtomtest/service.svc"
                  binding="customBinding"bindingConfiguration="mtomSoapBinding"
                  contract="WCFMTOM.IService1"/>
      </service>
    </services>
 
    <bindings>
      <customBinding>
        <bindingname="mtomSoapBinding">         
          <mtomMessageEncodingmessageVersion="Soap12"/>
          <httpsTransportmaxReceivedMessageSize="2000000000"/>
        </binding>
      </customBinding>
    </bindings>
 
    <behaviors>
      <serviceBehaviors>
        <behaviorname="ServiceBehavior">
          <serviceDebugincludeExceptionDetailInFaults="True"/>
          <serviceMetadatahttpsGetEnabled="true"/>
        </behavior>
      </serviceBehaviors>
    </behaviors>
 
  </system.serviceModel>

And here comes the question. Inside of "sendData" method i could get the values of two parameters(req.param1,req.param2). But as you can see I couldn't get the binary value of req.binaryData field. It is null. I was expecting to see the binary data that is coming from the request. Am i missing something? What am i doing wrong?