I just noticed that my pangolin performance panp4n system (driver 2.4.4)
boots in 32-bit mode:
$ uname -m
i686
instead of the 64-bit mode as I am sure it used to do.
this is a fully up-to-date system
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=9.10
DISTRIB_CODENAME=karmic
DISTRIB_DESCRIPTION="Ubuntu 9.10"

0. What did I do wrong?
1. how do I boot into 64-bit mode?
2. how do I make sure that I always boot into the 64-bit mode?

thanks