Hi!
I'm having a similar problem, with
http:// and only with some sites. I don't have proxies/firewalls in between but with a webserver in my LAN (Apache 1.3.12) I get a FileNotFoundException, but with the url of my ISP (and hosted by my ISP) there's no problem at all, though for other sites not being hosted by my isp I can't seem to avoid a FileNotFoundException.
Every sites are accessible through any ordinary browser with proxy settings off, i.e., direct connection to internet.
Any hints?!