I recently had to deploy this via GP and found a nifty tool at http://vnced.sourceforge.net/ Look for the "VNCed UltraVNC MSI Creator". It's a simple java app that gives you a GUI with most of the standard UltraVNC config options and then you just click a button and it spits out a deployable MSI. Has worked absolutely flawlessly on 1300+ computers here.
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