uPnP port forwarding problem

[okg]

I have StrongDC++ 2.21 + router Zyxel P-330W_EE_V3.60(AMJ.2)D0

DC is configured to be accessed via uPnP portforwarding.
DC shows no NAT related problems and can connect to a hub, but cannot search/download.
The uPnp checking utility (http://www.codeproject.com/KB/IP/PortForward.aspx) ,as an independent way to check the router, “says” the port forwarding is configured in the router correctly.

After(if) the router is configured manually (not via uPnp) to the same ports forwarded, everything works perfectly.

Why do I think the problem is not in the router?
Because eMule, a torrent client and many other third party apps utilizing the same uPnp from the same PC in the same router work fine always.

Indirect proof of the problem is when I have several interfaces up on the same PC (for instance loopback interface is up at 10.x.x.x), strong DC always shows “NAT related error”

The problem was in some previous versions as well.