  In a recent paper we introduced a multivariable generalisation of the Bessel
polynomials, depending on one extra parameter, and related to the so-called
hyperbolic Sutherland model with external Morse potential. In this paper we
obtain a corresponding multivariable generalisation of a well-known
orthogonality relation for the (one-variable) Bessel polynomials due to Krall
and Frink.
