How to display Warning messages in BADI ME_PROCESS_REQ_CUST?

Hi,

I have implemented BADI ME_PROCESS_REQ_CUST and coded necessary logic according to my requirement in Method PROCESS_ITEM.

On a certain condition , I need to display a Warning message.

I have written the code as follows:--

message w001(00) with 'XYZ'.

It didnt work.

Then, I included the message in message class ZPBS, and coded as follows.

message w012(zpbs).

But, still it didnt work..

Can u guys please guide me what I need to do?

Thanks,

Shivaa....