Sending Soap fault message to SAP

Hi SapAll.

I have got a situation where in an Idoc to Webservice Synchronous using BPM.WHEN PI call web service & web service get response then PI is sending the response to SAP RFM (Remote function module).but I also need to handle the failure case when PI gets Fault execution message back from Web service then PI need to send the same fault message to RFM-Exception structure.

I have

can any one help me in briefing the steps for this.

Regards.

Jagdish