Xml Namespace

Hi All,
Is the xml request correct?

<?xml version="1.0" encoding="UTF-8"?> 03 100001 000104637[/size] [SIZE=1] [/size]

the xml namespace declared and with prefix “tns” for namespaces "http://www.XXXX.com". But those xml tag ( SourceID, MessageTpye…) are not belong to namespace "http://www.XXXX.com". correct me if i am wrong

This client claimed that they are following the W3C standard in doing design. I am doubt of it as base on the example above, the xmlns should put it to default namespace right?

If they defined as xmlns:tns=http://www.XXXX.com”, then they should passes in all xml tags with tns: prefix. ( tns:SourceID, tns:MessageType…) . correct me if I am wrong.