changing alignment of built-in boolean

[invalidemail@aerojockey.com]

Is it possible, in GNAT, to force the built-in Boolean type to use
4-byte (32-bit) alignment?  Reason: I have to interface some Ada code
to a package that insists on 32-bit variables on 4-byte-aligned
addresses.

Feel free to suggest some other strategy for accomplishing this, though
I'd prefer not to make extensive changes to the Ada code (such as
changing it to use a subtype of Boolean).

I'm using GNAT 3.15p on HPUX.

Thanks.