I've been happily using AWS SES and Chilkat V 9.5.0 to send emails from our Web-sites for the past 2 years. AWS has now changed to using Signature V4 which relies on an IAM user. Has anyone got this working correctly?

From looking at the Com functions, I have included the following lines of code:
Code:
        // Signature V4
        Set ComPrecomputedSha256 of hoAuthAws to C_SES_Password
        Set ComSignatureVersion of hoAuthAws    to "AWS4"
I am getting the following error when I test with the Chilkat example, on the following line:
Code:
         Get ComFullRequestFormUrlEncoded of hoRest "POST" "/" to sResponseXml
Error:
Code:
  <ErrorResponse xmlns="http://ses.amazonaws.com/doc/2010-12-01/">
    <Error>
      <Type>Sender</Type>
      <Code>SignatureDoesNotMatch</Code>
      <Message>The request signature we calculated does not match the signature you provided. Check your AWS Secret Access Key and signing method. Consult the service documentation for details.
   
  The Canonical String for this request should have been
  'POST
  /
  content-type:application/x-www-form-urlencoded
  host:email.us-west-2.amazonaws.com
  x-amz-content-sha256:eda47a4cbba1cd70d2f11e65c5b83bb67905f5e5239ded38fa1f0b294721fe51
  x-amz-date:20210331T042521Z
   
  content-type;host;x-amz-content-sha256;x-amz-date
  eda47a4cbba1cd70d2f11e65c5b83bb67905f5e5239ded38fa1f0b294721fe51'
   
  The String-to-Sign should have been
  'AWS4-HMAC-SHA256
  20210331T042521Z
  20210331/us-west-2/ses/aws4_request
  b7d9127f45423f023be8e5206eb882dc590c709d135d8dc3de69639e5c705842'
  </Message>
    </Error>
    <RequestId>bd54d217-5889-4cbb-a177-1a01ba0e7698</RequestId>
  </ErrorResponse>
I'd be grateful for any suggestions,

Ian