create a new table entry

Hi

My point of concern is i have to insert a new message (Application Area M7, Message No. 433 'The "delivery completed" indicator is set for the purchase order item')

I have checked the tables, the tables are T100 and T160M.

My ques. is how do i insert this message in tables and what all linkages and configurations i need to make so as it displays an error message while dong GR for a PO with Delivery completed indicator ticked.

Can this job be done by a MM consultant itself or need of ABAPer is required.

Pls suggest.

Thanks in advance...