Span Video Playback Across Two Monitors on Geforce 5600

Hi guys,
I'd like to know how to span a video I'm playing across two monitors so I can get a bigger image. If I try to drag the windowed video player so it spans across two screens, the video only appears in on of the screen. I then played with the "full screen video" setting but it only allows clone. Please advise, thank you.

edit: I've just found a weird way to make it work. Have one video player open and play something then have the another video player play the video I want. The second video player does exactly what I want it to do; the video will split in two halves if i drag it toward the middle, will split if i do full screen and each monitor will display one half. Does anyone have an explanation for this behavior? Is there a more "legitimate" way of doing this?