ATP- Confirm full Case

Hello,

We are on 4.7V of SAP. I have a business scenario wherein a product Base unit of measure is "EA", but we want to ship the products in complete cases.

So, if 1 CS = 10 EA and we have 12 EA's in stock. Customer places order for 2 CS, ATP should confirm only 1 CS in this situation as the stock is not enough to ship 2 CS.

Please help me figure out how to acheive this in SAP.

Thank you in advance.

-Naga