When typing, my cursor jumps around like crazy, highlighting paragraphs, jumping back words, and making it impossible to type normally. MacBook4,1 (whatever that means), Mac OS X 10.5.8 (9L31a). I have searched high and low for what this could be, and only come up with one or two mentions of it, with no real resolution. To give you an example of what happens, here is the first sentence rewritten without correction:

normally.When typing, my cursor jumps zy, highlighting paargraphs, jumping back words, making it impossible to typeararound like cr