How to implement Microsoft Access boolean (YESNO) fieldtype in PostgreSQL ?

I am have some difficulties converting the Microsoft field of type
YESNO (which is a simple boolean true/false) to something that is
compatible with PostgreSQL.

I have tried with both boolean, bit(1) and even integer to try and get
it to work but with no success - Access see the boolean and bit(1) as
"text" fields.

This mean that I am not able to use the built-in form input fields for
the "YESNO" field type.

Anyone with any ideas on how to get around this?

Thank's Jesper K. Pedersen