One time customer

Hai Guys,

This is regarding one time customer. I had created an one time customer, made the fields - City and telephone as mandatory as per client's requirement.

When we make a sales order, the system pops up the form to be filled, in that these fields are not mandatory. Where does the system pick that form whose header reads as "Address from Master Data for Sold-To-Party (Document Header)"?

Where I have to make settings to make the fields in that Address as mandatory?

regards,

Maheshwaran. I