JSON stringify associative array returns empty array - use {} instead of new Array()

gistfile1.js

//JSON.stringify an associative array using the Array object --> does not work  
var array1 = new Array();
array1['a'] = { x : 1, y : 2 };

console.log(array1);
//outputs : [ a: { x: 1, y: 2 } ]

console.log(JSON.stringify(array1));
//outputs : []

//JSON.stringify associative array using {} --> works!
var array2 = {};
array2['b'] = { x : 1, y : 2 };

console.log(array2);
//outputs : { b: { x: 1, y: 2 } }
console.log(JSON.stringify(array2));
//outputs : {"b":{"x":1,"y":2}}

which breaks any usage with PHP and other back end scripts - so wrong.

"{}" creates and object, not an array. In JS there are no associative arrays, you can only use objects for that matter.