bind classless slave from microsoft dns classful SOA?

[Michael Hare]

Bind-users;

I have been asked to slave a /24 from a microsoft SOA, however, their 
authority for the /24 is false in that they really only have authority 
to 192/26.

Am I correct in that there is no way to slave said zone 
[x.y.z.in-addr.arpa] but serve it as a different zone 
[192/26.x.y.z.in-addr.arpa] without relying on some outside scripts to 
do the translation?

For what it's worth, I am running the 9.8X series of BIND.

Thanks-
-Michael