IIOP.NET (version 1.9.0.final) casts port numbers in corbaloc URLs to short integers. This means that you can not utilize the full port number range (<= 65535) as the casting results in overflow exception for high ports. AFAIK tcp and udp ports are unsigned 16 bit values, so I don't see a reason why IIOP.NET should impose this limit - esp. when other CORBA implementations (TAO, OmniORB, java's org.omg.CORBA) can handle the whole unsigned 16 bit port range.
The attached patch just replaces "short" port casts and arguments to "ushort" ones.