Duplicate namespace definitions are not removed

[Benjamin Bender]

Hi I'm using Axis2 for Java and I try to send messages with the following content and
the following style between the server and a client

  <soapenv:Header xmlns:wsa="http://schemas.xmlsoap.org/ws/2004/08/addressing">
    <wsa:EndpointReference>
      <wsa:Address>
        http://localhost:5988/root/cimv2:Linux_OperatingSystem
      </wsa:Address>
      <wsa:ReferenceParameters
       xmlns:linux_os="http://localhost:8080/WSDM/Linux_OperatingSystem.xsd">
        <linux_os:CreationClassName>
          Linux_OperatingSystem
        </linux_os:CreationClassName>
        <linux_os:CSCreationClassName>
          Linux_ComputerSystem
        </linux_os:CSCreationClassName>
        <linux_os:CSName>localhost.localdomain</linux_os:CSName>
        <linux_os:Name>localhost.localdomain</linux_os:Name>
      </wsa:ReferenceParameters>
    </wsa:EndpointReference>
        ...
  </soapenv:Header>

But if I try to construct this EndpointReference or any other OMElement then
namespace definitions that are defined a second time in a subelement are not
removed from the subelements. I can only construct the following:

  <soapenv:Header xmlns:wsa="http://schemas.xmlsoap.org/ws/2004/08/addressing">
    <wsa:EndpointReference>
      <wsa:Address>
        http://localhost:5988/root/cimv2:Linux_OperatingSystem
      </wsa:Address>
      <wsa:ReferenceParameters xmlns:linux_os="http://localhost:8080/WSDM/Linux_OperatingSystem.xsd">
        <linux_os:CreationClassName xmlns:linux_os="http://localhost:8080/WSDM/Linux_OperatingSystem.xsd">
          Linux_OperatingSystem
        </linux_os:CreationClassName>
        <linux_os:CSCreationClassName xmlns:linux_os="http://localhost:8080/WSDM/Linux_OperatingSystem.xsd">
          Linux_ComputerSystem
        </linux_os:CSCreationClassName>
        <linux_os:CSName xmlns:linux_os="http://localhost:8080/WSDM/Linux_OperatingSystem.xsd">
          localhost.localdomain
        </linux_os:CSName>
        <linux_os:Name xmlns:linux_os="http://localhost:8080/WSDM/Linux_OperatingSystem.xsd">
          localhost.localdomain
        </linux_os:Name>
      </wsa:ReferenceParameters>
    </wsa:EndpointReference>
        ...
  </soapenv:Header>

My problem is that the xmlns:linux_os is still defined in every subelement of wsa:ReferenceParameters although
xmlns:linux_os is already defined in wsa:ReferenceParameters. This makes the message larger than it has to be.

Can anybody tell me how I can build a message like in the first sample or is it a bug in Axis that the namespace
definitions of the subelements are not removed. I don't have the problem with the definition of the xmlns:wsa, here
the namespace definition is removed in the subelements. The problem appears only if an OMElement declares more than
one namespace.

Any hint is welcome.
Thanks,
Ben