Qty Rounding in PO

Hi All

I want to do rounding in the existing unit of measure. e.g. my requirement generated is 33 EA and 1 Pac = 10 EA. If i take PAC as ordering unit, system creates PO of 3 PAC. This is fine absolutely. I want rounding in base unit of measurement. e.g. requirement generated is 33 EA. I want to fix EA as ordering unit and PO qty should be rounded to 30 EA.

I mean if i take alternative UOM as ordering unit, it works fine. If my base UOM and ordering UOM is same, rounding doesn't take place.

Is it possible to do rounding at UOM in which requirement got generated??? Requirement generated in EA, and i want to do rounding at EA not PAC.

Gud answer will be awarded fully.

Regards

Kapil