Islam really hasn't changed at all in that regard, they still believe in "Jinn" (demons and such) magic spells, etc. You even see much mention of it in Ishaq's sira, "Sirat Rasul Allah"(the life of Mohammad) The only source of all that is known about Mohammad and therefore Islam. No Mohammad- no Islam. Any Muslim who denies Ishaq's writings has to then deny Islam and Mohammad, not only because all that is known about Mohammad comes from Ishaqs work, butr because all other Islamic "scholars" after Ishaq base their material on Ishaq work as well.
http://muhammadanism.org/Canon_Sell/default.htm
you can also download THE LIFE OF MUHAMMAD published in 1913, written by Edward, Canon Sell, a Fellow of the University of Madras, India. The original source notes are fascinating and irrefutable.
Sell wrote a number of works on islam, all available on PDF