Lubuntu when booting computer, log in screen shows 'default' session instead of last used session

Binary package hint: lxdm

Description: Ubuntu lucid (development branch)
Release: 10.04

lxdm:
  Installed: 0.2.0~svn2307+git20100408-0ubuntu1~ppa2
  Candidate: 0.2.0~svn2307+git20100408-0ubuntu1~ppa2
  Version table:
 *** 0.2.0~svn2307+git20100408-0ubuntu1~ppa2 0
        500 http://ppa.launchpad.net/lubuntu-desktop/ppa/ubuntu/ lucid/main Packages
        100 /var/lib/dpkg/status
     0.2.0~svn2307+git20100209-0ubuntu2 0
        500 http://gb.archive.ubuntu.com/ubuntu/ lucid/universe Packages

What I expected to happen: when booting computer for the first time, I used to reach the log-in screen, and then find the last used session (openbox session in my case) in the session field. Then I logged in and used my customised desktop

What actually happened. When I rebooted after the upgrade last night, the session field in the log in screen showed 'default' as the session. When I logged in, got error message, and ended up with LXDE session. When logging out and logging in again without rebooting, expected behaviour occured (openbox session)

Minimal steps to show bug: Reboot computer. Log in.

I'm assuming that this change in behaviour is related to the change from gdm to lxdm