An interesting bug I found in my n800 is shown below:

The HTTP proxy settings have been entered, however they haven't been enabled- note the "Use Proxy" checkbox is not checked; and proxy details are greyed-out.

However, this doesn't quite work as expected. Upon connecting to a network, I get scenes like this:

Application manager cannot refresh Application lists.

Media cannot be streamed.

Feeds cannot be added to the Feed reader.

However, the web-browser will browse happily!

The way around this is to specify no proxy settings as follows:

This looks as if its a GConf problem- I'll check it out when I'm back on a computer. I'm finding the Maemo subversion repository a bit of a labyrinth though!

Update: This bug has already been reported on the Maemo bugzilla.