Cs3 Canvas Guides

[aaron-marine]

so in photoshop CS, i used to fill one layer with a solid color, and by doing so i would drag 2 guides out of the rulers (vertical and horizontal). as i pull these guides across the canvas, they would snap to the center of my solid layer, giving me a crosshair on the canvas to make it easier to center elements in different layers when needed. In CS3 I cant get my guids to snap to the center of that solid layer, or the center of any layer for that matter. Does anybody know of how to do this in CS3?

thanks.

ps. I will forever miss those linking chains right on the layers in photoshop CS