OS im using Windows 7 SP1, web browser Firefox and also playing on offline portable version, the whip(attack) and arrow keys works fine except the jump(key).
Really strange, there's no difference in the code between the whip key and the jump key. I don't know why it happens. Try to use the whip key as the jump key to see if it works. When you use the jump, hold down the key at least 1 second to make a full jump.
