Using a recent Camino 2.1a1pre nightly... STR: 0) Visit (for example) http://ad.doubleclick.net in Camino to ensure you can reach it. 1) Add "127.0.0.1 [tab] ad.doubleclick.net" to your /etc/hosts file with your favourite text editor and save the changes. 2) Repeat step 0 and observe its failure. 3) Comment out the hosts file entry and save. 4) Repeat step 0. ER: Success. AR: Failure. This works in Safari 5 and Firefox 3.6, but I'd be mildly shocked if this was really a problem in Camino code.
So, it didn't always fail for me, but I've been able to reproduce this. I tested the url in comment 0 and caminobrowser.org in addition to a couple of domains on the local dev server. In my tests, I loaded the url(s), closed the tab/window, edited the hosts file and closed it. Loaded the url(s) again. Two observations: 1. I have seen failures after step 1 in comment 0 - url not blocked when it should be blocked. Even a force reload sometimes failed. 2. I've seen the exact same failures with a fairly recent Namoroka build (fx 3.6 nightly).
I haven't seen one of these failures in a long time, although I also haven't taken anything *out* of my hosts file in a long time. Not sure what might have changed, though.