networking startup broken in Feisty

Binary package hint: network-manager

In Edgy I'd either removed or disabled networkmanager and had a wireless and a
wired interface configured as auto in /etc/network/interfaces, which worked fine.

Updating to Feisty has enabled networkmanager, which breaks this. It starts up at
some stage in multiuser mode and clobbers the network connexion (which is made
OK in single user mode). I can't at that stage persuade networkmanager to do anything
sensible. It won't connect to my wireless net and if I use ifup on the interface it
the connexion is broken a short time later by (I assume) networkmanager. I had to
kill the NM processes.

This is on a Thinkpad X30 with bcm43xx and e100 networking, but I doubt that's
relevant.