There is also
Hostiles List which can simply be added to the LW preferences folder.
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However I'm not sure if it is compatible with 4.8.1, edit:
http://www.gnutellaforums.com/263954-post9.html
You could at least use those ip's to block manually.
BTW LW 4.8.1 was my favorite version for a long time, IMHO better than versions up to at least 4.12 or perhaps 4.14.