rem: element._revert = new Effect.Move(element, { x: -left_offset, y: -top_offset, duration: dur}); 
add: Draggable._revertCache[element] = new Effect.Move(element, { x: -left_offset, y: -top_offset, duration: dur}); 
context:       reverteffect: function(element, top_offset, left_offset) {        var dur = Math.sqrt(Math.abs(top_offset^2)+Math.abs(left_offset^2))*0.02;        element._revert = new Effect.Move(element, { x: -left_offset, y: -top_offset, duration: dur});      },
meta: 7994	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/7994/bd1ac4786a539a5d509de64f60a003cc15cce8c9/dragdrop.js/buggy/src/dragdrop.js