Bob is right. It has been recognised as a problem for some time - indeed we have members in countries with none of their ports listed at all!
At one time someone (probably a past webmaster) was keeping a list of requests/suggestons, but it was not taken forward at that time and, for a variety of reasons, it unlikely that the issue will be resolved in the near future. It is still, however, very much in mind for when a site upgrade becomes possible.