I'm using an old 32 bit laptop (Samsung N120) running Debian testing; up until recently I've been able to configure it so when I close the lid it turns off the screen, but leaves the laptop running. With a recent update (possibly this morning, but I couldn't swear to it) I'm not able to do this any more -- when I close the lid, the laptop suspends.
I'm using xfce, with power management through xfce4-power-management. At this point, I've got it configured so that the power, sleep, and hibernate buttons are all set to "do nothing" and the laptop lid is set to "switch off display" for both battery and AC power. The power manager seems to be active, as when I turn on "handle brightness keys" I can adjust brightness, while I if I turn that off I can not. The current version of xfce-power-management is 1.4.4-4. I've tried both going back to 1.4.1-1 and forward to 1.6.0-1 with no difference. To the best of my knowledge I have no screensavers or screen lockers installed. Any thoughts where I should look?