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

And what could be the reason for the different behaviours of the different feeds? Also, if Firefox cannot download something, it becomes obvious. But here you might believe that there are simply no new articles. It is tricky, I know. Just an idea: how does this work in Thunderbird? That should be more similar.