1) Download the tar.gz file from vnc from http://www.realvnc.com/download.html
2) gunzip <filename.tar.gz>
3) tar -xvf filename.tar
4) cd to vnc* directory which was extracted from the tar
4) Run vncinstall as ./vncinstall /usr/local/bin
5) Run the cp command for the classes as shown in the README file
6) Run ./vncpasswd and enter a passwd
7) Run ./vncserver:X for start servers on display X

The above process with only give you an xterm when you log in using VNC. If you want the entire Desktop, go to the .vnc directory of the user and edit the xstartup file, to change twm to dtwm and change the PATH env variable to PATH=/usr/dt/bin:$PATH;export PATH. Your good to go.
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