Error while parsing an XML stream: 'undeclared namespace prefix'

Hi,

i have a requirement like comsuming a webservice from the .NET system, for that i have created a client proxy usign ABAP.

When i am executing that, i am getting following error

SOAP:1.001 CX_SXML_PARSE_ERROR:SXML reader/writer exception.Error while parsing an XML stream: 'undeclared namespace prefix'.

can any one help me, thanks in advance.

Regards,

Kumar