Completely wrong keyboard-layout after logon to GNOME
If you are using gnome as default desktop environment and are affected by completely wrong keyboard-layout after logon to gnome (http://bugs.debian.org/476727) use the following workaround:
Directly in the line before /etc/X11/Xsession of $HOME/.vnc/xstartup add the line
export XKL_XMODMAP_DISABLE=1