Refreshing feeds offline

When trying to refresh feeds (feed toolbar or context menu) with a disabled internet connection, I experience two behaviours:

1. Refreshing ends almost immediately.
http://newsfox.mozdev.org/rss/rss.xml

2. Refreshing only ends after the feed refresh timeout.
http://newsrss.bbc.co.uk/rss/newsonline_uk_edition/uk_politics/rss.xml

I tried to refresh feeds without an active internet connection to see if I get a warning or not. Actually, I do not, thus I have every reason to believe that the refreshing was successful. This impression is even stronger if there are deleted articles, which disappear exactly the way they should.

NewsFox 1.0.3b2

Re: Refreshing feeds offline

However, when the user checked work offline, refreshing should still work to the extent of wiping the deleted feeds in order to clean up the feeds pane. Actually, if there were a way to wipe the feeds pane without proper refreshing, I would use it quite often. The way I do it now is "Work offline" and then "Refresh". But I use SeaMonkey, where "offline mode" is shown by an icon in the statusbar (and clicking on it changes it). I did not find this in Firefox 2.