A few people read it almost two years ago when I first wrote it but then I had been asked to keep it hidden. Given the current climate in IT security I frankly doubt that my research from 2003 could cause anyone a headache so here is the (now of historical interest) paper entitled Sobig-G: addressing the weaknesses in Sobig-F.
Ultimately it has very little to do with Sobig-F and a lot about efficient distribution of viral code updates.