I am going over to Europe in a few months, and I would like to be able to use my N900 with some 3G prepaid data package. Unfortunately, they all use IPv4. Is there any elegant way to get IPv4 working as well over the 3G modem, without uninstalling the IPV6 'hack'? I have a 3G modem for my netbook, so this is not extremely important, but would be nice.

I assume you mean the dual connections documented at: http://n900-ipv6.garage.maemo.org/

You can just move the files in /etc/network to a temporary location.

I read that page a while ago, before the nat64 thing.
So do I just have to move the files in /etc/network to a temporary location, and I magically get IPv4 connectivity again? Then I just move them back when I need IPv6? Anything else? Do I move ALL the files in /etc/network ?

Nvm, I looked at the files there and I guess only the nat64 up and down must be moved, not all the files. But is moving them enough?

Oh, if you have the files /etc/network/if-up.d/nat64-up and /etc/network/if-down.d/nat64-down, you're using the libnat64 library.

You shouldn't need to do anything with files in that case. You should have two cell phone connections listed in your list of internet connections. The one with the red "v6" text in the icon is the IPv6 connection, the one with the blue lines in the icon is the regular v4 connection. The libnat64 library only takes effect when using the IPv6 connection.

Does this make sense to you? I don't have my n900 on me, so I feel like my explanation might be a little off.

It makes sense, but I never seen the blue connection since I installed the IPv6. I see it in the connections list in Settings/Connections, but it never appears when I want to connect to 3G.

That's odd, it should show up in the list of connections whenever you have a cell signal. You can try removing your v6 connection by running: "/usr/bin/register_3g_ipv6 deinstall"

If you want to re-add the v6 connection after you deinstall, you just need to run "/usr/bin/register_3g_ipv6 install"

FYI, T-Mobile is having a hardware issue in the lab where the beta is hosted... working to resolve it

FYI, the IPv6 Beta is fixed now

Just curious, are the N900 owners the main testers for the IPv6 beta?