[CentOS] gphoto2 and Nikon Coolpix 990/995

Hi all,

I've got a CentOS 5.4 box and am trying to use it to control  either
of the two old cameras we've got, one being Nikon Coolpix 990 and the
other Nikon Coolpix 995. Accessing either I get the following message:

----------------------------------------------------
*** Error ***
An error occurred in the io-library ('Could not claim the USB
device'): Could not claim interface 0 (Operation not permitted). Make
sure no other program or kernel module (such as sdc2xx, stv680,
spca50x) is using the device and you have read/write access to the
device.
ERROR: Could not capture.
*** Error (-53: 'Could not claim the USB device') ***
----------------------------------------------------

Any idea what this could be about?

By the way, about a year ago I did manage to use a Linux machine to
control one of these cameras (the 990, I believe).

Thanks in advance.

Boris.