Mousedown pageX , pageY is not same after mousemove pageX pageY , happens randomly
<p>I want to create a multi select box (click and drag at empty space then will have a blue div ), but the click and drag is inconsistent and i cant find out the problem.</p>

<p>try to drag from a empty space that is around the bottom right , top right or bottom left and you can see that the light blue box didnt actually start from the point where the mouse down</p>

<p><a href="http://jsfiddle.net/wizztjh/jk4Uc/7/" rel="nofollow">http://jsfiddle.net/wizztjh/jk4Uc/7/</a></p>
