I have a problem remoting my home desktop through tightvnc,

My home desktop and n900 have different network, because i want to be able to monitor it while i'm away
So I followed this port forwarding guide precisely

http://portforward.com/english/route.../Tight_VNC.htm

I've set up my static ip address, put it on the router port forward setting just like the guide says.
Tight vnc is already on the firewall exceptions,

But it still won't connect over the internet on my N900,
Am i missing something here?

Oh and i'm connecting it from n900 using external IP address of the router