Hmm, I don't use a unix OS, so I may be wrong, but is 640x480 the default really??? As far as I know, the default is usually 1024 x 768. I myself experienced a crash when taking a photo ('E') on any resolution not on the exact aspect ratio. Try it again with that aspect ratio, and try the size I said above. If it doesn't work, I guess its a unix thing maybe...?