Cannot change sound volume with keyboard while sound indicator is open

Binary package hint: indicator-sound

Step to reproduce:
 - hit the volume button of the keyboard => the volume is changed
 - left click the sound indicator
 - (don't close the sound indicator panel) hit the volume button of the keyboard => the volume IS not changed

I don't know if this behaviour is expected but at least it sounds strange to me.

In case it depends on the keyboard, I am using "Microsoft Confort Curve 2000 v1.0"

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: indicator-sound 0.3.9-0ubuntu2
ProcVersionSignature: Ubuntu 2.6.35-14.20-generic 2.6.35
Uname: Linux 2.6.35-14-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
CheckboxSubmission: 89866d158f7fd641409854e92433a2e3
CheckboxSystem: 2a6f54df59af338184485e85cbcf0d32
Date: Tue Aug 10 01:35:52 2010
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Alpha amd64 (20100602.2)
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: indicator-sound