DSD in IMG menu

Hi all.

I'm starting to investigate the Direct Store Delivery.

I have 2 systems (both SAP 6.0). In one of them in the IMG I can see the menu point "Direct Store Delivery" under "Logistics Execution", but in the other one this point doesn't appear.

Please, can anybody give any idea about the configuration of the DSD?

Is there any relatioship with SAP ECC Extensions?

Tranks in advance and regards.

Santiago