Validation for IL taxes applied on PO

Hey all,

I wonder if anyone is aware of any validation available for the Indian local taxes applied on purchase order. This tax information has to be applied before approving a PO, and sometimes the end-users forget to do it. I would like to add a validation to check if the taxes have been applied before submitting the PO for approval. Is this something that can be done thru the forms personalizations?

Thanks,

Mari