FIELD OF THE INVENTION The present invention relates to a taste masked orally disintegrating composition, preferably an orally disintegrating tablet of Imatinib or pharmaceutically acceptable salt thereof, comprising a) Imatinib or pharmaceutically acceptable salts thereof, b) a taste-masking polymer, c) a super disintegrant and optionally other excipients. BACKGROUND OF THE INVENTION Imatinib mesylate is chemically designated as 4-(4-methylpiperazin-l-ylmethyl)-N- [4-methyl-3-(4-pyridin-3-yl) pyrimidin-2-ylamino) phenyl]-benzamide methane sulfonate and its structural formula is Imatinib is a protein-tyrosine kinase inhibitor, especially useful in the treatment of various types of cancer and can also be used for the treatment of atherosclerosis, thrombosis, restenosis, or fibrosis. Thus Imatinib is used for the treatment of non- malignant diseases. Imatinib is usually administered orally in the form of suitable salt, e.g., in the form of Imatinib mesylate. Imatinib mesylate is a white to off white to brownish or yellow tinged crystalline powder with an unpleasant, bitter or otherwise disagreeable taste when administered orally. Imatinib mesylate is soluble in aqueous buffers