[рони]

Ещё самокат ))) ...

function compare(arr1, arr2){
    if(arr1.length !== arr2.length) return false;
    arr1.sort();
    arr2.sort();
    var i = Math.random();
    return arr1.join(i) == arr2.join(i)  ;
};
var a = ['a','b','c','c'], c = ['b','c','a','a'], d = ['b','c','c','a'];
alert([compare(a,c),compare(a,d)]);