How to check if two arrays are equal with JavaScript?

#short
#javascript
var a = [1, 2, 3];
var b = [3, 2, 1];
var c = new Array(1, 2, 3);

alert(a == b + "|" + b == c);

demo
How can I check these array for equality and get a method which returns true if they are equal?
Does jQuery offer any method for this?