A. Inside the vnc session press < F8 > and then choose "Exit Viewer". Tested this on xvnc4viewer 4.1.1+X4.3.0-2 , running on Debian Etch (currently testing).
Q. How to exit the full screen mode in NX?
A. Inside the nxclient session, go to the top right corner. Left mouse clicking there will iconify the NX session. Tested this on nxclient 2.1.0-17, running on Debian Etch (currently testing).
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