Keyboard slows way down at GDM login

[onionparadise]

So, I think this may be similar to the problem described in http://forums.linuxmint.com/viewtopic.php?f=55&t=93286&p=543409&hilit=keyboard+gdm#p543409. This is very recent--I shut down my computer earlier this evening, not having updated anything, everything was working fine. I go to turn on the computer an hour and a half later, and it appears that my keyboard does not work at the GDM login screen. After several passes through the reboot cycle and booting into netroot to try to verify that the keyboard does in fact work, I got so frustrated at the GDM login screen that I just held down the first letter of my password in frustration. And lo, it types! I found that the keyboard did in fact work, but only if I held each key down for at least a second, maybe a second and a half. The keyboard works perfectly fine everywhere else--the problem is confined to the GDM login screen. Why did this happen? And how can I fix it?

I'm running Mint 11 64-bit on a Sony Vaio VPCEE42FX.

Cheers,
Onion