The invention relates to the delta and epsilon crystal form of the methanesulfonic acid addition salt of 4-(4-methylpiperazin-1-ylmethyl)-N-[4-methyl-3-(4-(pyridin-3-yl)pyrimidin-2 -ylamino)phenyl]-benzamide (the compound of formula I, see below), certain processes for their preparation, pharmaceutical compositions containing these crystal forms, and their use in diagnostic methods or for the therapeutic treatment of warm-blooded animals, and their use as an intermediate or for the preparation of pharmaceutical preparations for use in diagnostic methods or for the therapeutic treatment of warm-blooded animals, especially humans.