me 28 user exit

Hi,

could you please tell me how to capture PO Item delivery date values into internal table of present Purchase order from table EKET-EINDT when PO create/edit and PO release(ME28).

I can't get PO document number unless PO saved. ? how to get screen values of EKET in me21 transaction for item delev. dates?

My SAP version is 3.1i

thanks in advance.

Leela