Hack `mouseup` outside the window in IE 7/8

I understand the event mouseupfor the window simply does not exist for IE 7 and 8. I was wondering if anyone had found a job for this or if it was possible.

I am currently working on a project in which the user can click, drag to draw a line, and if the user drags outside the window and then click on the mouse, the drawing transaction will be canceled.