How to make VNC Server work with ubuntu-desktop without xfce

install these packages

# apt-get install gnome-panel gnome-settings-daemon metacity nautilus gnome-terminal

and use this xstartup file

#!/bin/sh

export XKL_XMODMAP_DISABLE=1
unset SESSION_MANAGER
unset DBUS_SESSION_BUS_ADDRESS

[ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup
[ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources
xsetroot -solid grey
vncconfig -iconic &

gnome-panel &
gnome-settings-daemon &
metacity &
nautilus &
gnome-terminal &

I had to add gnome-session & prior to gnome-panel & to get any window management to work. Without it, I could only view the default desktop.