µTorrent 1.9 alpha 15380 - setting single outgoing and incoming port

[Kiwi]

For µTorrent 1.9 alpha 15380, I have a query.

I wonder why is it that when I set the µTorrent options to be using only a single port for both outgoing and incoming connections (so that I can use QOS settings to set priority on it), I can't seem to get it work for my Windows XP x64 system. It does work on my existing Windows XP x32 system. I have checked settings on both µTorrent's configuration windows and they are already the same.

Can anyone help me out on this?

Thanks in advance.