function urldecode( str ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Philip Peterson
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: AJ
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: Brett Zamir (http://brettz9.blogspot.com)
    // +      input by: travc
    // +      input by: Brett Zamir (http://brettz9.blogspot.com)
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // %          note 1: info on what encoding functions to use from: http://xkr.us/articles/javascript/encode-compare/
    // *     example 1: urldecode('Kevin+van+Zonneveld%21');
    // *     returns 1: 'Kevin van Zonneveld!'
    // *     example 2: urldecode('http%3A%2F%2Fkevin.vanzonneveld.net%2F');
    // *     returns 2: 'http://kevin.vanzonneveld.net/'
    // *     example 3: urldecode('http%3A%2F%2Fwww.google.nl%2Fsearch%3Fq%3Dphp.js%26ie%3Dutf-8%26oe%3Dutf-8%26aq%3Dt%26rls%3Dcom.ubuntu%3Aen-US%3Aunofficial%26client%3Dfirefox-a');
    // *     returns 3: 'http://www.google.nl/search?q=php.js&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a'
    
    var histogram = {};
    var ret = str.toString();
    
    var replacer = function(search, replace, str) {
        var tmp_arr = [];
        tmp_arr = str.split(search);
        return tmp_arr.join(replace);
    };
    
    // The histogram is identical to the one in urlencode.
    histogram["'"]   = '%27';
    histogram['(']   = '%28';
    histogram[')']   = '%29';
    histogram['*']   = '%2A';
    histogram['~']   = '%7E';
    histogram['!']   = '%21';
    histogram['%20'] = '+';
    histogram['\u20AC'] = '%80';
    histogram['\u0081'] = '%81';
    histogram['\u201A'] = '%82';
    histogram['\u0192'] = '%83';
    histogram['\u201E'] = '%84';
    histogram['\u2026'] = '%85';
    histogram['\u2020'] = '%86';
    histogram['\u2021'] = '%87';
    histogram['\u02C6'] = '%88';
    histogram['\u2030'] = '%89';
    histogram['\u0160'] = '%8A';
    histogram['\u2039'] = '%8B';
    histogram['\u0152'] = '%8C';
    histogram['\u008D'] = '%8D';
    histogram['\u017D'] = '%8E';
    histogram['\u008F'] = '%8F';
    histogram['\u0090'] = '%90';
    histogram['\u2018'] = '%91';
    histogram['\u2019'] = '%92';
    histogram['\u201C'] = '%93';
    histogram['\u201D'] = '%94';
    histogram['\u2022'] = '%95';
    histogram['\u2013'] = '%96';
    histogram['\u2014'] = '%97';
    histogram['\u02DC'] = '%98';
    histogram['\u2122'] = '%99';
    histogram['\u0161'] = '%9A';
    histogram['\u203A'] = '%9B';
    histogram['\u0153'] = '%9C';
    histogram['\u009D'] = '%9D';
    histogram['\u017E'] = '%9E';
    histogram['\u0178'] = '%9F';
 
    for (replace in histogram) {
        search = histogram[replace]; // Switch order when decoding
        ret = replacer(search, replace, ret) // Custom replace. No regexing   
    }
    
    // End with decodeURIComponent, which most resembles PHP's encoding functions
    ret = decodeURIComponent(ret);
 
    return ret;
}