I just compiled and tested app-misc/interceptty on my Athlon64. Seems to work just fine. Please add ~amd64 to the keywords for this package. Thank you.
Starting up echo server...OK Testing echo server...OK Starting up tty server...OK Testing tty server...OK Starting Unix socket server...OK Starting Unix socket client...OK Testing Unix sockets...OK Starting file descriptor server...OK Testing file descriptors...OK Starting Inet server on port 9999...OK Starting Inet client on port 9999...OK Testing Internet socket server...OK Looks good - InCVS