(Maitre'D 2005, from Service Pack 3 and later versions of Maitre'D)
P.O.S. Control / Employees / Configuration / Order / Command
Send on Positive Total Only:
Enable this option in the Fast-Food Configuration to force a manager Takeover
for transactions where the total is brought back down to $ 0.00 or negative
before it can be closed with the Send, Print or Close buttons.