The error seems to be connected to the result limit. Instead of setting a low result limit you should rather set it to an enormous number (like 8000) so it is never reached. I did this and the error didn´t occur ever since although i did a lot of popular searches.

And to the virus topic. You should NEVER, EVER download an executable file from gnutella. There is no executable at all related to phex. Anything besides the zip and the java-files must be fake. But perhaps I have to repeat it again:

NEVER DOWNLOAD any EXECUTABLE from gnutella. It will almost SURELY CONATAIN A VIRUS.