Hi Friend,
If the same destination route is learned as O and also as IA , route via Frame-relay link will always be preferred as it is intra area route.
So I don't think it is possible in this kind of setup unless and untill you change the way areas are configured and on the other note OSPF only do equal cost load balancing so even the destination learned have 2 paths with O but uneuqal cost it will not load balance till the time to tweak the cost in such a way that the detination comes with 2 equal path.
HTH
Ankur