Restart Spaces is a quick and easy work-around of some common Spaces issues. Restart Spaces simply quits and restarts the Dock (Spaces is part of the Dock application, it is also quit and restarted along with the Dock). Restart Spaces is a FreeWare AppleScript App for Mac OS X 10.5. I don't have an Intel Mac readily available to test, could someone verify if it works OK on Intel & add to the comments?
Mac OS X 10.5 or later