Ok, I've got back to my home machine, since I was puzzled by the different behaviour I got in work.

Home: Lynx 2.8.5 or Konqueror 2.2.1 on Mandrake
Work: Konqy 2.2.1 on Solaris (from source)

Searching on "pare" or "parenthesis" from home, using lynx gives me a "502 Server Hangup" warning. This is then followed by a mostly empty page:

                                 Server Hangup
     _________________________________________________________________

   Description: Server Hangup
     _________________________________________________________________

With Konqy, I don't get the inital warning, just the error page.

I've also tried it with "flibble", and get the same results. So I now suspect that there's a bug in the "zero hits" handler of the search engine (which explains why the problem on "paren" went away as soon as I reported it. Typical ;-)