JavaScript objects + arrays help


#1
<head>
	<meta charset="utf-8" />
	<title>Ex.01.05 - </title>
	<style>
	</style>
	<script>
		function geraArrayPts(numPts, limX, limY){
			var i, array=[], ponto={};
			for(i=0; i<numPts; i++){
				ponto.x = Math.floor((Math.random()*limX)+1);
				ponto.y = Math.floor((Math.random()*limY)+1);
				array.push(ponto);
			}
			return array;
		}
		function mostraArray(array){
			var i;
			for(i=0; i< array.length; i++) document.write(array[i].x+', '+array[i].y+'<br />');
		}
	</script>
</head>
<body>
	<script>
	mostraArray(geraArrayPts(5, 300, 300));
	</script>
</body>

Can anyone explain why the outputs are all the same?