No clue. Perhaps Desdemona would like to hazard a guess on that.
And here's a quote from another article about this mural:
Italian Muslims Demand Destruction Of Offensive Painting
According to The Times, British Islamic scholar Gai Eaton also minimized the impact of the 600-year-old image, saying, "The mural is particularly offensive, but that does not mean that we as Muslims can demand its destruction, or the destruction of Dante's Divine Comedy either.
"Muslims must be allowed to blow off steam, but beyond that we must put up with these things. It is not as if this is a contemporary work. It represents medieval Christian prejudice against Muslims at the height of the Islamic threat to Western Europe."
Well, excuse me, but it seems that we are pretty much as far, if not farther, along the road to being threatened by moslems as the west was in medieval times. At least then, the threat wasn't world-wide, but contained in smaller areas. Now however, I can't think of many areas in the world that aren't being subjected to invasion by moslems, frankly, except for the arctic and antarctic.