I guess I’ve found a graphic bug in OS X, not quite a big deal but it’s so rare that it worth mentioning.

In order to secure my laptop I wanted it to ask a password after waking from sleep. By default, Mac OS X doesn’t ask for anything; when you open the laptop, you return to the previously opened session without notice.

Go to the security panel in the system preferences and enable the first option to “require a password to wake this computer from sleep.”

And here is the bug: when the laptop wakes from sleep, it shows a login windows asking for a password but instead of entering it, click on “change user”; the cube animation starts but without any background texture and you’ll see garbage graphics instead.

I haven’t see anything about this bug, so I’ll submit it to Apple.