gthumb cant find images on canon eos300d

[Simon]

When I plug in my digital camera a box pops up telling me that there are 
images on the camera, and do I want to import them. I say yes, and an 
'import photos' window appears which promptly tells me that there are no 
images on the device. No other errors are displayed, but I cant get it 
to find the images.

There are images on the device, and they copy over fine on windows. I 
also have no problem importing images on the same machine from my Sony 
DSC-F717 camera, but not with the Canon