Comment 5 for bug 689359

If it happens when scanning from the gimp as well, then it is most certainly not a problem with simple-scan but with sane-backends/the scanner driver. You might reassign the ticket here, but writing to sane-devel http://lists.alioth.debian.org/mailman/listinfo/sane-devel will more likely result in useful feedback.
Please report back here whatever you achieve. Thanks!