Changing array subscripting to zero-offset

Hello everyone -

Array columns are, by default, 1-offset in their
subscripting.  Since I usually am calling postgres
from a language with zero-offset, I would prefer
that postgres conform to that.  The online
documentation hints that this may be configurable
but I haven't been able to find how this is done.

Any help is greatly appreciated,
Erin Sheldon