Does somebody know where the last name PINSEAU comes from please

I need help because my dad told me his great great grandmothers fathers last name was PINSEAU so I decided to search for the origin because it is not a common last name so I was searching for the origin but I did not have one it said that the name was not in there data base so please help me

The name looks/sounds french to me... and it seems so from the family tree databases at Rootsweb too:
RootsWeb's WorldConnect Project: RootsWeb's WorldConnect Project Global Search (http://worldconnect.rootsweb.com/cgi-bin/igm.cgi?surname=pinseau&given=)