[CentOS] (In)(x)sane privilege/access issue

Sun Sep 26 03:22:27 UTC 2010
Mark <mhullrich at gmail.com>

I just picked up a new HP OfficeJet J3680 all-in-one (because, as
previously posted, my 4315 broke), and I was able to install the
printer using the latest hplip's hp-setup command, BUT:

My sane:

libsane-hpaio.x86_64                       1.6.7-4.1.el5.4             installed
sane-backends.x86_64                       1.0.18-5.el5                installed
sane-backends-devel.i386                   1.0.18-5.el5                installed
sane-backends-devel.x86_64                 1.0.18-5.el5                installed
sane-backends-libs.i386                    1.0.18-5.el5                installed
sane-backends-libs.x86_64                  1.0.18-5.el5                installed
sane-frontends.x86_64                      1.0.14-1.2.2                installed
xsane.x86_64                               0.991-5.el5                 installed
xsane-gimp.x86_64                          0.991-5.el5                 installed

doesn't recognize that there is a scanner out there and only loads the
interface for my old ScanJet 3300C:

[mar at marichter ~]$ lsusb
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 012: ID 03f0:0205 Hewlett-Packard ScanJet 3300c
Bus 002 Device 006: ID 04f9:0033 Brother Industries, Ltd
Bus 002 Device 001: ID 0000:0000

In fact, the new scanner doesn't even show up unless:

[mar at marichter ~]$ sudo lsusb
[sudo] password for mar:
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 015: ID 03f0:3112 Hewlett-Packard
Bus 002 Device 012: ID 03f0:0205 Hewlett-Packard ScanJet 3300c
Bus 002 Device 006: ID 04f9:0033 Brother Industries, Ltd
Bus 002 Device 001: ID 0000:0000

If I run xsane from the command line as root (i.e., with sudo), then
it works, but then I also get that WARNING DANGER WILL ROBINSON
message, which is both annoying and probably likely to cause problems
with file permissions on my scans.

So, how do I (a non-root user) get x/sane to see the new USB device
when it only appears to visible to the root user?  What am I missing?

Thanks.

Mark