  We prove that the quantum SO(3)-invariant of an arbitrary 3-manifold $M$ is
always an algebraic integer, if the order of the quantum parameter is co-prime
with the order of the torsion part of $H_1(M,\BZ)$. An even stronger
integrality, known as cyclotomic integrality, was established by Habiro for
integral homology 3-spheres. Here we generalize Habiro's result to all rational
homology 3-spheres.
