Forums Bug Reports cannot change default DCC Server port 59

Thanks westor for your quickply! :-)
Unfortunately this seems not to be a problem of mIRC settings!
I already changed the settings a lot :-)
On the other hand it's not a NAT problem too - the portforwarding,
of my FritzBox 90 works.
Anyway I must say that everything with DCCdccrks nicely,
only that I cannot successfully change the DCC server port.
The machine I'm testing it with is in the same LAN and always tries
to connect to port 59.
Even if I use something like: /dcc fserve ip-adress:notthedefaultport

I actually feel like it's a mIRC bug:
Found some post where someone is using a script to be able
to change the port - too difficult for me more...