This somehow works, but the results can not be compared to what is possible using cinepaint -> qpfstmo. There is a Gimp plugin called "Exposure Blend" (http://turtle.as.arizona.edu/jdsmith/exposure_blend.php) to automate what is described in the article you cited above. However, it seems more that the Gimp way just results in a little bit lighter image compared to the normal image taken by the camera.