As a Catholic the idea of any mortal being "incorruptible" in death strikes me as a romantic notion which I would like to believe, but of which I have my doubts. Although all things are possible through God, it has always been my feeling that the manner of burial had more to do with the preservation of the body than much else. Poor Saint Bernadette, for instance, was disinterred innumerable times and the record of what was found does sound pretty remarkable, but because everyone involved were no doubt people of strong faith, their testimony could have been somewhat colored. I will admit though it makes an interesting read.
St. Bernadette in death-
Story of disinterments of Saint Bernadette of Lourdes-1909-1919-1925
http://paranormal.about.com/gi/dynamic/offsite.htm?zi=1/XJ/Ya&sdn=paranormal&cdn=newsissues&tm=14&gps=128_155_1003_518&f=10&tt=14&bt=1&bts=1&st=32&zu=http%3A//www.catholicpilgrims.com/lourdes/ba_bernadette_intro.htm