Is it possible to install Mail 4.4 from Snow Leopard on Leopard?

[Velorium]

My friend wants Exchange support on mail but is on Leopard. I don't completely feel comfortable installing Snow Leopard on their machine because they don't have a backup, so I was wondering for my peace of mind before tomorrow if anybody had any experience with installing Mail from the Snow Leopard install disc onto Leopard.

Thanks!

 

[Intell]

It cannot be done. The Snow Leopard Mail calls certain things that Leopard does not have. Thus, it would crash before starting.