diff -ur Mail-SpamAssassin-3.4.0/lib/Mail/SpamAssassin/Plugin/URIDNSBL.pm Mail-SpamAssassin-3.4.0_fix/lib/Mail/SpamAssassin/Plugin/URIDNSBL.pm
--- Mail-SpamAssassin-3.4.0/lib/Mail/SpamAssassin/Plugin/URIDNSBL.pm	2014-02-07 09:36:27.000000000 +0100
+++ Mail-SpamAssassin-3.4.0_fix/lib/Mail/SpamAssassin/Plugin/URIDNSBL.pm	2014-02-13 17:24:09.259369721 +0100
@@ -416,6 +416,8 @@
   while (my($uri, $info) = each %{$uris}) {
     # we want to skip mailto: uris
     next if ($uri =~ /^mailto:/i);
+    # we want to skip so-files, they are not url's
+    next if ($uri =~ /\.so$/);
 
     # no hosts/domains were found via this uri, so skip
     next unless ($info->{hosts});