B2B Toolkit 2.0 issue with x12 997

Hi

after moving to B2B toolkit 2.0 I'm facing an issue for processing the 997 x12 received from customers. The error from the Receiver EDISeparator is

Message could not be forwarded to the JCA adapter. Reason: while trying to invoke the method com.sap.aii.adapter.ediseparator.ra.x12.AcknowledgementMessage.getInterchangeSenderID() of a null object loaded from local variable responseMessage

The process is that the 997 is received and translated into an ALEAUD message was working on Toolkit 1.0 . We're not using TPM.