  In this paper we shall prove that the subalgebra generated over the integers
by the divided powers of the Drinfeld generators $x_r^{\pm}$ of the Kac-Moody
algebra of type $A_2^{(2)}$ is an integral form (strictly smaller than
Mitzman's (see [Mi]) of the enveloping algebra, we shall exhibit a basis
generalizing the one provided by Garland in [G] for the untwisted affine
Kac-Moody algebras, and we shall determine explicitly the commutation
relations. Moreover we prove that both in the untwisted and in the twisted case
the positive (respectively negative) imaginary part of the integral form is an
algebra of polynomials over the integers.
