Further to my earlier posts, I've been improving the documentation for the Inhibit and UnInhibit methods, and really testing them hard. There's now a testing utility, gnome-power-inhibit-test in g-p-m CVS that allows you to play with multiple Inhibits and other issues. The testing utility shows how easy it is to add the DBUS methods into your program. The same methods can be used with GNOME Screensaver (but you'll have to change the service and interface names to ScreenSaver). Trying to suspend when we have an multiple Inhibit requests gives us this. 
And a single inhibit: 
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hughsie
Richard has over 10 years of experience developing open source software. He is the maintainer of GNOME Software, PackageKit, GNOME Packagekit, GNOME Power Manager, GNOME Color Manager, colord, and UPower and also contributes to many other projects and opensource standards. Richard has three main areas of interest on the free desktop, color management, package management, and power management.
Richard graduated a few years ago from the University of Surrey with a Masters in Electronics Engineering. He now works for Red Hat in the desktop group, and also manages a company selling open source calibration equipment. Richard's outside interests include taking photos and eating good food.
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That's excellent! Maybe “because it is” instead of just “because”, because that will make a full sentence.