# killall -HUP dnsmasq
That should re-read its configuration.
Then you could try if DNS is working:
# nslookup www.google.com

nslookup should show it connects to 127.0.0.1 and after that it resolves the address. If it doesn't dnsmasq does not know a working outside DNS-server or does not have route to it.

# route
to see routes
and see if there is any /var/run/resolv.conf* files and if, what is inside of them.

unfortunately I am 'unauthorised' to enter those commands; but I'm unable to become root, since I can't download rootsh :/

thanks for the continuing support (:

I'd just like to let it known - for the inevitable later googles - that I've managed to fix the problem. I set DNS to Google's Public ones for BOTH the N900 and my router; I can now update and download successfully.

Many thanks to everyone that helped me out here.

I have the same problem. But if I use the browser to go to https://downloads.maemo.nokia.com I get an Acces Denied error immediately. So apparently when I use the browser the host can be resolved. Strange, no?
I want to try the solution bjjperrott suggested here, but how do I set the DNS in the N900?

I get "Access Denied" too from that address, but can download fine from the repos. If you change it to "http://downloads.nokia.com" does that work?

No, that doesn't work. I now get a 404 not found. I only changed the "downloads.maemo.nokia.com" in the URLSs to "downloads.nokia.com" and left the rest of the URLs intact. or should I just make the URL "http://downloads.nokia.com/"?

Dear Bjjperrott,

Can you kindly explain how to achieve changing the DNS to Google's Public ones for both the N900 and router? The router...do I have to change the gateway on my access point? I couldn't really understand your statment.