Bogus Keycodes from Linux host to virtualbox client

[Mark Neidorff <mark@neidorff.com>]

I'm running Lenny and Virtualbox 3.0.12.  The client OS in VB is XP.  
Yesterday, I wanted to listen to a web based music stream, so in lenny I 
connected to a radio station's stream using "movie player."  Music plays, 
everything works.  Then I started virtualbox/XP/MS Word.  Every few seconds, 
word reacted as if someone had pressed the "alt" key on the keyboard (set 
focus to the menus rather than the regular text input.  I didn't close XP or 
virtualbox down, but I switched to the host and stopped "movie player".  The 
problem went away.

Have you seen this problem before?  Do you have any idea which bit of software 
the problem belongs to?  Where do I find a fix and/or where do I report the 
bug?

Thanks for any help,

Mark