The short story is: Tom's keyboard sends all that when he presses caps
lock:

press: 0x3a 0xe0 0x66
repeat: 0x3a
release: 0xba 0xe0 0xe6

0xe0 0x66 happens to be the "favorites" key on his keyboard with
internet navigation keys.  I thus believe there's a bug in his keyboard
that needs to be filtered at the kernel level.

The long story can be read on http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=594089

Tom Vier, le Mon 13 Sep 2010 14:07:29 -0400, a écrit :

Here's xev from Stable. It looks like in Testing that some of the extra 
key codes that show up in showkey are getting interpreted as additional 
key presses in Testing's xorg but not Stable's.

Yes, as I said in a previous mail, squeeze Xorg now interprets the
internet scancodes by default, while it wouldn't in lenny and previous,
thus not showing the bug.

Samuel