If you run into Windows 7 or Server 2008 machines which won't let you send Ctrl-Alt-Del from KVNC, I have a solution:
If that value is 0, you won't be able to "send" that key combo, period. Luckily it's an instant-fix registry change (not unlike the "disable local inputs" VNC registry setting... not that we use this very often, ahem). I've built a quick two-line script to remedy this and stuck it into Policy Management so I can keep this opened up.
The more you know, musical chime, star flying across the screen, warm fuzzy feeling, etc.
Cool. I'm going to use this and get some fuzzy feelings too.
I believe the phrase you were looking for, GreyDuck, was "BOOM! Fixed it."