diff -Nur wiithon/core.py wiithon_new/core.py
--- wiithon/core.py	2009-12-05 16:18:27.000000000 +0100
+++ wiithon_new/core.py	2009-12-05 16:18:54.000000000 +0100
@@ -34,7 +34,9 @@
         salida = []
         for linea in lineas:
             cachos = linea.strip().split(config.SEPARADOR)
-            cachos[1] = util.decode(cachos[1],guessBytesCharset(cachos[1]))
+	    charSet = guessBytesCharset(cachos[1])
+            if charSet is not None:
+		cachos[1] = util.decode(cachos[1],charSet)
             idgame = util.decode(cachos[0])
             sql = util.decode("idgame=='%s' and idParticion='%s'" % (idgame, particion.idParticion))
             juego = session.query(Juego).filter(sql).first()