Droid 2 Proximity Sensor Issue?

[Phydeaux]

The proximity sensor on my Droid 2 tends to freak out if I return to the desktop during a phonecall. The notification area flashes green (I presume this is to alert me to the fact that I'm on a live call). The moment I bring my finger anywhere near the screen, the screen blacks out. When I move my finger away, the screen comes back. It's like some sort of grand tease and makes it impossible to hang up, since any attempt to control the phone leads to the screen turning dark. Since this is my first Android phone, I'm posting this in hopes that this is a well known issue, or that I might be doing something stupid.