Port mapping failure

I keep getting a "Port mapping failure, miniupnp error: 501" error. I've checked the router (Linksys WRT120N) settings and the port 2234+2235 are setup correctly. UPnP is enabled also. Below is the entire Port Forwarding log:

Initializing UPnP
Device list found
http://192.168.1.1:80/igd.xml, InternetGatewayDevice, found
Device XML found.
Adding mapping for port 2235
Found own address to be 192.168.1.100
Port mapping failure, miniupnp error: 501

Any suggestions? Thank you in advanced. And thank you for the considerate design structure throughout QT! Really lovely :)

Did you manually set up a port forward for 2234 and 2235? If so the router might just be reporting that it can't remap the port. Error 501 doesn't seem to a problem with the miniupnp library itself, your router appears to be producing this error code, which vaguely just means "action failed".