Sender port of IDOC when sent from PO is showing up as TRFC in ECC

Hi Folks,

I suppose this might be a common issue. When I send an IDOC from PO to ECC and select the following options in the IDOC receiver receiver Channel I see the sender port is populated as TRFC instead PO sender port. This looks to be a default instead can't we have the actual Port of PO populated?

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Regards

Kalyan.