Are they LW clients do you know? Some other gnutella programs don't translate their messages properly over to LW; eg: whilst the searches will go thru ok, LW doesn't decode them properly. This is a guess as I am aware there are some issues between gnutella clients. Which ones? Not absolutely certain, but BearShare seems to be one. Some of the older gnutella clients also. Some characters don't translate properly either.

After 10 mins of checking, I only saw one with @ at the end but nothing like you saw. Possibility of lack of language support on your side.

In my monitor I see also japanese, chinese, korean & moslem.