Microsoft released portrptr.exe recently. Port Reporter runs as a service on Windows 2000/XP/2003 systems, logging sockets used to the c:\winnt\system32\logfiles\portreporter directory. Here are sample records:
The first is an FTP control channel. The last three are FTP data channels. I am not sure about the second entry but the source port is the same as that used for the first FTP data channel.