In this paper we have obtained some novel generating functions of Fn(α, β−α; x) – a modified form of the extended Jacobi polynomial Fn(α, β; x) – by means of Weisner’s group-theoretic method with the suitable interpretation of the parameter α of the polynomial under consideration. Moreover, we have shown that the generating functions involving the extended Jacobi polynomial Fn(α, β; x) derived in [2], obtained by using the same Weisner’s group-theoretic method with the suitable interpretation of (α, β), can be easily obtained from our results. Finally, a group-theoretic method of obtaining general bilateral generating relation from general unilateral generating relation is also discussed.