Timeout error in TightVNC Viewer

I get a message saying 'the connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.' I'm connecting to an RHEL 6.4 box in Hong Kong. When I connect via ssh (putty) , it normally takes a few seconds longer than connecting to anything in the US. How do I increase the connection timeout in VNC?

Thanks,

Calvin