How to send to SAP a Kanban Empty pulse from an External Warehouse system

Hi Gurus

MY company use from some years an external (no SAP) WM system, using RF technology, This system was implemented before SAP released RFcapabilities with 4.6 release. This external system can create Idocs and send it to SAP using SAP Business- connector to permit a fully integration between teh two systems. Now I want set-up on teh Warehouse external system soem Kanban features, starting from the Kanban Empty pulse (PKBC transaction in SAP).

My question is very easy: Does exist an Idoc, which permit to receive this pulse from an external system and perform automatically teh operation on SAP ???

If the Idoc doesn't exist. Is there in your opinion another way to solve this issue.

Thanks in advabnce for your help !!!

Claudio