I am using the latest nightly build: Mozilla/5.0 (X11; U; Linux 2.2.5-15 i686; en-US; m16) Gecko/20000502 build ID:2000050215 and I try and connect to a site that is in DNS but isn't running a webserver I will not get an error message saying "cannot connect" or anything like that. It just says "Document: Done (xx.yy secs)" This problem does not occur on the NT version of Mozilla. The Linux version should generate an error message like the NT version does.
I can confirm this with a Linux CVS build from today. If you start Mozilla pointed at such a machine/page, the URL bar remains blank (one of the signs of a bad load), but no popup alert is shown (although the console logs an error about loading the page).
*** Bug 34210 has been marked as a duplicate of this bug. ***
make sure you are running the latest build. my pull from today displays the message.
whoops. not proxy related...