Unity3d Network, port is not opened

Unity3d Network, port is not opened

I try to create a simple network example over the internet. This is the code:
void OnGUI()
{
if (Network.isServer)
{
GUI.Label(new Rect(10, 10, 100, 30), "Server is started");
}
else
{
if (GUI.Button(new Rect(10, 10, 100, 30), "Create Server"))
{
Network.InitializeServer(10, 25000, true);
}
}
}
Then I turn off the firewall and antivirus programs. I forward the port
25000 into my local IP address.
Then I run the program and click on "Create Server" button to make it
running and go to http://www.yougetsignal.com/tools/open-ports/ to check
whether my port is opened. The result is always "closed". What did I do
wrong?
NOTE:
I tested the port with other application to make sure that it is not
blocked by ISP.
This is what I got by using netstat http://screencast.com/t/qzArfnxxH
Thanks