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I believe that above dragging problem for me at some of my computers is caused by the Magic Track pad after all, in different updates its get very touchy, and now if i only ever so slightly touche it, i can drag. In the end it might after all have been me who did something wrong and not apple, - still i blame apple for not making it obvious enough, im regard myself as superuser and it took me forever to make it work - "apple, just works" (just not all the time, and only if you know how), anyhow in the end i/we learned to live with it, not perfect, but still way better than any other computer alternatives.
