Controlling DISPLAY for vncserver connections

Hi,

I have an fc17 box with vncserver working as a regular user on display :13. However, when I connect to it from a RealVNC client and try to open chrome, it opens on my real desktop, not the vnc desktop. How do I control this?

I'm using the default gnome with fc17. When I go to the Applications menu and open a gnome-terminal, it opens correctly on the vnc desktop. However, chrome opens on the main desktop.

I'd also like to be able to use firefox, but when I try to start it, it's already running on my main desktop, so firefox complains and fails to start on the vnc desktop.

Is it possible to access my main display from vnc?

Also, is there a known problem with setting the geometry with fc17 and the tigervnc-server? It always defaults to the geometry of my main display, not the size that I've chosen on the command-line when starting the server.

Thanks,
Alex