Comment 15 for bug 205767

Well, same problem with a Canon PowerShot A80.

For "permanent workaround":

First check your camera ID with lsusb:
[...]
Bus 001 Device 005: ID 04a9:309a Canon, Inc. PowerShot A80
[...]

After that, edit the file /etc/udev/rules.d/40-permissions.rules and search for
LABEL="usb_serial_start"

You should add this line (and change you idVendor and idProduct!)
ATTRS{idVendor}=="04a9", ATTRS{idProduct}=="309a", \
                                        MODE="0660", GROUP="plugdev"

(I've found the solution here: http://ubuntuforums.org/showthread.php?t=784864)

And that's all !