Changing customer then no Sales order aknowlegement

I have come across an odd problem. A salesman has put an order in Vantage
5.2 an then after a few days changed to customer as we are now dealing
direct with the customers customer. The original sales order has had a job
created and Vantage and lets you change to customer you are selling to. The
problem is when you go to print a new sales order acknowledgement you can't
print one or preview (no error message).

Anyone else came across this, unfortunately salespeople only worry about
there little world and don't realize that changing the customer name will
impact on production and scheduling. I personally feel that the changing of
customer name after a sales order is entered should be lock and grayed out.