Commerceone wmmarketconnect adapter


My client has commerceone marketconnect adapter.

I was using SAP Business connector’s marketconnect adapter to post data to service pub.marketconnect.transport/receiveEnvelope.
But now we want to migrate to another middleware of SAP.

I am trying to access it by sending payload in HTTP Post but I get exception (envelope field is null) in HTTP Response.

The Input of service is envelope object.
I think while communicating using Business connector, Marketset connector was generating envelope.

How can I generate envelope in absence of such adapter or is it mandatory to have such adapter?

How can I send it through HTTP?