Middleware Must Return All Responses Immediately

Responses to 'send_message', 'get_message_status', and 'drop_message' must be returned immediately.

When Middleware receives a message via 'send_message' operation and it needs to do some time-consuming processing, Middleware must return the response with 'sent', 'sending', or 'failed' status and then continue with processing in another thread or process.

Middleware implementation must not engage in any long processing before SOAP response has been returned to OFSC.

This is because Middleware will not receive any more messages on this message scenario step until it returns the SOAP response. Blocking during the SOAP call means that the messages will be processed very slowly and likely slower than they are generated.