Hi,

I just had this problem. I had previously had BlessN900, flashlight-applet and mbarcode installed. I removed BlessN900 before I installed kernel-power, as I'd heard there were problems between them, but afterwards the camera application (cssu) showed just a blank screen. Flashlight-applet gave an error that the camera was in use by another application.

I did:

sudo gainroot
apt-get remove fcam-drivers

and rebooted, and it was fixed. It seems that the fcam drivers weren't removed when I uninstalled Bless.

Hope that helps anyone who finds themselves in the same situation.