I Need a Help on a language problem - Mailing list pgsql-ports

I'm from Colombia S.A, here we speak spanish, I need to insert
data in an information system that works with postgresql,
the problem is that when I need to inserta a word like niño
or canción postgres put ni?o instead of niño or canci?n instead of
canción, I need to know hoy can I put spanish words without having
this kind of problems.

Thanks
Mauricio O.