Odčeštění textu Javascriptem

cz2en = function(str) {
if (typeof str != "undefined" &&
str != null &&
str != "") {
// platny retezec
var czLower = "áäčďéěëíňóöřšťúůüýž";
var czUpper = "ÁÄČĎÉĚËÍŇÓÖŘŠŤÚŮÜÝŽ";
var enLower = "aacdeeeinoorstuuuyz";
var enUpper = "AACDEEEINOORSTUUUYZ";
var s = str;
var re = null;
for (var i = 0; i < czLower.length; i++) {
re = new RegExp(czLower.charAt(i), "g");
s = s.replace(re, enLower.charAt(i));
re = new RegExp(czUpper.charAt(i), "g");
s = s.replace(re, enUpper.charAt(i));
}
return s;
}
return str;
}