Something else to add the this thread. If you have a pressure flush toilet you can not pour water in it and make it flush. If you don't know if it is a pressure flush toilet or not, lift the tank cover and if you can see water it is not a pressure flush toilet. If you lift the tank cover and see a tank it is a pressure flush toilet.

I do not know if all pressure flush toilets suffer from this affliction or not, i had this conversation just a few days ago with a friend of mine and none of his toilets worked by pouring water in it when he lost water pressure.