Não consigo trabalhar com webcam (VirtualBox Ubuntu 11.10 no Mac OSX 10.6.8)

Question

Instalei o Guest Additions, instalei o isight-firmware-tools usando o arquivo AppleUSBVideoSupport, mas ainda não consigo acessar a webcam iSight.

Quando eu inicio o > vlc v4l2: /// dev / video0, recebo os seguintes erros:

Blocked: call to unsetenv("DBUS_ACTIVATION_ADDRESS")
Blocked: call to unsetenv("DBUS_ACTIVATION_BUS_TYPE")
[0x92d492c] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
Blocked: call to setlocale(6, "")
Blocked: call to setlocale(6, "")

(process:2922): Gtk-WARNING **: Locale not supported by C library.
    Using the fallback 'C' locale.

(vlc:2922): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap",

(vlc:2922): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap",

(vlc:2922): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap",

(vlc:2922): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap",
[0x963287c] v4l2 demux error: VIDIOC_STREAMON failed
[0x963287c] v4l2 demux error: cannot set input (Device or resource busy)
[0x96430a4] v4l2 access error: VIDIOC_STREAMON failed
[0x96430a4] v4l2 access error: cannot set input (Device or resource busy)
[0x9371104] main input error: open of 'v4l2:///dev/video0' failed: (null)