bsfilter bsfilter-1.0.18.ruby1.9.rc5 workaround that dies with "ArgumentError: invalid byte sequence"

gistfile1.diff

--- bsfilter.1.0.18rc5  Sun Mar 10 03:03:03 2013
+++ bsfilter	Mon Jul  1 02:52:54 2013
@@ -933,24 +933,27 @@
       if (str.force_encoding('ASCII-8BIT') =~ reg_gb18030_possible)
         gb18030_possible = true
       end
-
-      if (str.encode('UTF-8', 'UTF-8') =~ reg_utf8)
-        @options["message-fh"].printf("lang ja utf8\n") if (@options["debug"])
-        return ["ja", "utf8"]
-      elsif (str.force_encoding('ASCII-8BIT') =~ reg_jis)
-        @options["message-fh"].printf("lang ja jis\n") if (@options["debug"])
-        return ["ja", "jis"]
-      elsif (str.encode('SHIFT_JIS', 'SHIFT_JIS') =~ reg_sjis)
-        @options["message-fh"].printf("lang ja sjis\n") if (@options["debug"])
-        return ["ja", "sjis"]
-      elsif (str.encode('EUC-JP', 'EUC-JP') =~ reg_euc)
-        if (gb18030_possible)
-          @options["message-fh"].printf("lang ja gb18030\n") if (@options["debug"])
-          return ["ja", "gb18030"]
-        else
-          @options["message-fh"].printf("lang ja euc\n") if (@options["debug"])
-          return ["ja", "euc"]
+      begin
+        if (str.encode('UTF-8', 'UTF-8') =~ reg_utf8)
+          @options["message-fh"].printf("lang ja utf8\n") if (@options["debug"])
+          return ["ja", "utf8"]
+        elsif (str.force_encoding('ASCII-8BIT') =~ reg_jis)
+          @options["message-fh"].printf("lang ja jis\n") if (@options["debug"])
+          return ["ja", "jis"]
+        elsif (str.encode('SHIFT_JIS', 'SHIFT_JIS') =~ reg_sjis)
+          @options["message-fh"].printf("lang ja sjis\n") if (@options["debug"])
+          return ["ja", "sjis"]
+        elsif (str.encode('EUC-JP', 'EUC-JP') =~ reg_euc)
+          if (gb18030_possible)
+            @options["message-fh"].printf("lang ja gb18030\n") if (@options["debug"])
+            return ["ja", "gb18030"]
+          else
+            @options["message-fh"].printf("lang ja euc\n") if (@options["debug"])
+            return ["ja", "euc"]
+          end
         end
+      rescue => err
+        p err
       end
     end
     return [nil, nil]