Idea: No waiting for customer in Chinese restaurant

In Sunday of Hong Kong, Chinese restaurant are often crowded with customer waiting for their seat, since it is a cheap way to kill time. However, many of us aren't patient person and can't stand the wait in the seats outside the restaurant while they don't want to lose the seat. Is there a solution for this dilemma?

I thereby propose my conceptual innovation here:

It work as simple as a software program, every time when a customer arrive, his /her phone, name and number of seats s/he will occupied, the software would assigned a customer number and printed a hardcopy as evidence. As seats become available, the waitor operate this system would click a button to increase the customer number in the database, it would then alter the customer through SMS via VoIP software like Skype or Ekiga with a pre-recorded message, or through a recorded voice message to phone in the database. Since it take time for customer to arrive to the restaurant, the system could held the seat for half hour(or any amount of time set in the software). Thus now customer no longer need to wait in front of restaurant.