Soap Envelope Parse Error

Hello..

I am a new comer in SOAP-WebService or something like that..
I try to call a procedure using SOAP-UI application.
But I have a problem here, it always return error message 'Could not parse the soap envelope.'
Where is the problem so that I always got the error?
I highly appreciate for your help.. Thanks

here is my code

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:aws="http://queue.amazonaws.com/doc/2009-02-01/">
   <soapenv:Header API Version 2009-02-01 5 Amazon Simple Queue Service API Reference API Versions xmlns:aws="http://security.amazonaws.com/doc/2007-01-01/">
 <aws:AWSAccessKeyId>-keyID-</aws:AWSAccessKeyId>
 <aws:Timestamp>2008-02-10T00:00:00Z</aws:Timestamp>
 <aws:Signature>-sign-</aws:Signature>
   </soapenv:Header>
   <soapenv:Body>
      <aws:CreateQueue>
         <aws:QueueName>My Queue</aws:QueueName>
         <aws:DefaultVisibilityTimeout>30</aws:DefaultVisibilityTimeout>
         <aws:Attribute>
            <aws:Name>Test</aws:Name>
            <aws:Value>Tes123</aws:Value>
         </aws:Attribute>
      </aws:CreateQueue>
   </soapenv:Body>
</soapenv:Envelope>