Comment 6 for bug 926064

Yup, just hit this bug myself while typing on the keyboard. I'm on Debian Wheezy.

$ apt-cache policy xscreensaver
xscreensaver:
  Installed: 5.15-3

$ lsusb
Bus 001 Device 002: ID 045e:00db Microsoft Corp. Natural Ergonomic Keyboard 4000 V1.0
Bus 005 Device 003: ID 046d:c531 Logitech, Inc.

I've noticed this problem before while reading a lengthy web page and only scrolling.
Both cases should inhibit the screensaver.
xinput detects scroll events (no need for moving the mouse) and of course, keypresses on a keyboard.

$ xinput list
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ Logitech USB Receiver id=8 [slave pointer (2)]
⎜ ↳ Logitech USB Receiver id=9 [slave pointer (2)]
⎜ ↳ Microsoft Natural® Ergonomic Keyboard 4000 id=11 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
    ↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
    ↳ Power Button id=6 [slave keyboard (3)]
    ↳ Power Button id=7 [slave keyboard (3)]
    ↳ Microsoft Natural® Ergonomic Keyboard 4000 id=10 [slave keyboard (3)]