XML Deserializer and Default Namespaces handling

[irwin]

Hello,
Recently I had to use the XmlSerializer object to deserialize one of the
objects in a project.
When I invoked Deserialize on the xml document containing the object
definition, I would get an exception from the XmlSerializer indicating the
root element was not expected.
This error was only resolved when the default namespace for the incoming xml
document was included in the constructor of the Deserializer.
However, the xml document did define a default namespace as is shown below:
<?xml version="1.0" encoding="IBM437"?>
<SubmitRsp
xmlns="http://www.3gpp.org/ftp/Specs/archive/23_series/23.140/schema/
REL-5-MM7-1-2">
<MM7Version>5.3.0</MM7Version>
<Status>
<StatusCode>1000</StatusCode>
<StatusText>Success</StatusText>
</Status>
<MessageID>20051118/10/C8******@192.168.0.121</MessageID>
</SubmitRsp>
So, why is it still necessary that I include a default namespace value in
the constructor of the XmlDeserializer (which is equal to the default
above).

Irwin