Not all the Japanese peers are good peers, but that's true for a number of countries I guess. In my connection lists I've posted for people having connection problems, I removed most Japanese hosts, only a few 'if any' left on the list from memory.
I've done the same thing as you at times, continually removed such hosts. If you desperately wanted to get rid of Japanese hosts full stop, you could ban all their ranges. lol
I've tried that too.
Just as a note, I find Phex tends to get a nice mix of European and USA hosts. Not sure why LW attracts them, both LW 4 & 5, perhaps because it IS LW.
But LW was designed to give some preference to connecting to LW and LW clones (such as Cabos), also for search results. This is a common trait for most gnutella clients to be set to favor their own kind when they can. My Phex just connected to 3 French, 1 UK and 1 USA, then later a 6th ultrapeer.
If you have a firewall that can ban ports such as Windows 7 firewall, I guess you could set up a disallow rule for port 6346 but this might also mean the possibility of missing out on some good hosts who are using port 6346 as a static port and not necessarily using Cabos or similar. But I would recommend banning port 27016 for both tcp and udp if you can, only LW spammers use that port. More on spam or bad addresses here
http://www.gnutellaforums.com/open-d...tml#post368141. Note: the technutopia hostiles document itself is not read by any version of LW 5 due to its older address format layout.
If you want a full list of Japanese ip's I can send you one privately. Or else send you the list I use for blocking many of them. The majority of Japanese ip addresses below the 200.x.x.x range are static and do not change.