Unmute system when headphones are plugged in?

When I upgraded my last laptop to Windows 7 I noticed that when I plugged my headphones in my system would unmute. If I checked the audio properties I'd see two bars, one for my system speakers that would remain muted, and another for the headphones that would be on. This doesn't happen with my new X201, and I was wondering if there was a way to get this back?