"IN" in a geometric database using data type "point"

Hi, i'm trying to request a database using data type "point" using keyword
"IN" with a list of point generated by PHP, like this:
'SELECT * FROM map WHERE position IN ((point(-1,-1), (point(1,-1),
point(1,1), point(-1,1))'
but this request returns me an error: operator doesn't exist point = point.
so i tried to use a path unstead of list of point like this:
'SELECT * FROM map WHERE position <@ path '(point(-1,-1), (point(1,-1),
point(1,1), point(-1,1))'
but this request returns me the point 0,0???

Is anybody have a suggestions?

Thanks.