Hi,
This has to do with the message exchange viewer and not the HTTP Monitor. The message exchange viewer validates for well-formed xml, it does not validate against the wsdl or schema files for the Interface. The request and response editors in the SOAP test step validate against the interface used to create the test step. I would say this is not a bug, but more of a feature request if you would like this for the message exchange viewer. You can use the schema compliance assertion for the test steps to check if the response is a valid response.
Regards,
Marcus
SmartBear Support
