@jcboy,
I'd agree with JCboy on the malware diagnosis - but not on the Mac conversion :-P
At my institution I manage a proxyserver so that students can login and get off campus access to resources that are restricted to on campus IP addresses. There is one piece of Malware called Secret Source really hates EZproxy (the the proxy software we use because they are both trying to do the same thing (rewrite web addresses in html pages to insert themselves between user and web site)
It sounds like your malware is rewriting your proxy config to a server that isn't online.
Have you got any malware/antivirus software that you can your machine with?