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I know this is in irrlicht-1.6 and the privious ones but I dunno if it's in the 1.7.1 version too
Bug: if you open the demo and choose burningsvideo 0.44 and you walk to a place where it's open str8 above you and you look str8 down on the floor and push S and hold it for a couple of secs you will fly like 10 meters high .
I think this is a bug because this trick doesn't work in Direct3D mode
Well, actually I have this (or a very similar) bug with Irrlicht 1.71 and in Direct3D 9 mode. There, if I press the jump button in the right intervall I can make a double or even a triple jump (like in mario).