getting postgres to emulate mysql/sqlserver bit datatype

Hi,
I am trying to port an app to postgres and have come up against a most
annoying problem. The app works with both mysql and sqlserver, who
both seem to have a bit datatype instead of a proper boolean like pg.
Alas, pg won't accept 1 and 0 for boolean... and npgsql won't convert
my numeric(1) into a boolean (and shouldn't either!). Is there any way
to force pg to accept 1 and 0 for boolean? I know it probably isn't
optimal, but hey. If there is a standard way to do this (and no,
rewriting is not an option) I'm all ears.
Cheers
Antoine