function utf8_encode ( argString ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Webtoolkit.info (http://www.webtoolkit.info/)
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: sowberry
    // +    tweaked by: Jack
    // +   bugfixed by: Onno Marsman
    // +   improved by: Yves Sucaet
    // +   bugfixed by: Onno Marsman
    // +   bugfixed by: Ulrich
    // *     example 1: utf8_encode('Kevin van Zonneveld');
    // *     returns 1: 'Kevin van Zonneveld'

    var string = (argString+''); // .replace(/\r\n/g, "\n").replace(/\r/g, "\n");

    var utftext = "";
    var start, end;
    var stringl = 0;

    start = end = 0;
    stringl = string.length;
    for (var n = 0; n < stringl; n++) {
        var c1 = string.charCodeAt(n);
        var enc = null;

        if (c1 < 128) {
            end++;
        } else if (c1 > 127 && c1 < 2048) {
            enc = String.fromCharCode((c1 >> 6) | 192) + String.fromCharCode((c1 & 63) | 128);
        } else {
            enc = String.fromCharCode((c1 >> 12) | 224) + String.fromCharCode(((c1 >> 6) & 63) | 128) + String.fromCharCode((c1 & 63) | 128);
        }
        if (enc !== null) {
            if (end > start) {
                utftext += string.substring(start, end);
            }
            utftext += enc;
            start = end = n+1;
        }
    }

    if (end > start) {
        utftext += string.substring(start, string.length);
    }

    return utftext;
}

function md5 (str) {
    // http://kevin.vanzonneveld.net
    // +   original by: Webtoolkit.info (http://www.webtoolkit.info/)
    // + namespaced by: Michael White (http://getsprink.com)
    // +    tweaked by: Jack
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: Brett Zamir (http://brett-zamir.me)
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // -    depends on: utf8_encode
    // *     example 1: md5('Kevin van Zonneveld');
    // *     returns 1: '6e658d4bfcb59cc13f96c14450ac40b9'

    var xl;

    var rotateLeft = function (lValue, iShiftBits) {
        return (lValue<<iShiftBits) | (lValue>>>(32-iShiftBits));
    };

    var addUnsigned = function (lX,lY) {
        var lX4,lY4,lX8,lY8,lResult;
        lX8 = (lX & 0x80000000);
        lY8 = (lY & 0x80000000);
        lX4 = (lX & 0x40000000);
        lY4 = (lY & 0x40000000);
        lResult = (lX & 0x3FFFFFFF)+(lY & 0x3FFFFFFF);
        if (lX4 & lY4) {
            return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
        }
        if (lX4 | lY4) {
            if (lResult & 0x40000000) {
                return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
            } else {
                return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
            }
        } else {
            return (lResult ^ lX8 ^ lY8);
        }
    };

    var _F = function (x,y,z) { return (x & y) | ((~x) & z); };
    var _G = function (x,y,z) { return (x & z) | (y & (~z)); };
    var _H = function (x,y,z) { return (x ^ y ^ z); };
    var _I = function (x,y,z) { return (y ^ (x | (~z))); };

    var _FF = function (a,b,c,d,x,s,ac) {
        a = addUnsigned(a, addUnsigned(addUnsigned(_F(b, c, d), x), ac));
        return addUnsigned(rotateLeft(a, s), b);
    };

    var _GG = function (a,b,c,d,x,s,ac) {
        a = addUnsigned(a, addUnsigned(addUnsigned(_G(b, c, d), x), ac));
        return addUnsigned(rotateLeft(a, s), b);
    };

    var _HH = function (a,b,c,d,x,s,ac) {
        a = addUnsigned(a, addUnsigned(addUnsigned(_H(b, c, d), x), ac));
        return addUnsigned(rotateLeft(a, s), b);
    };

    var _II = function (a,b,c,d,x,s,ac) {
        a = addUnsigned(a, addUnsigned(addUnsigned(_I(b, c, d), x), ac));
        return addUnsigned(rotateLeft(a, s), b);
    };

    var convertToWordArray = function (str) {
        var lWordCount;
        var lMessageLength = str.length;
        var lNumberOfWords_temp1=lMessageLength + 8;
        var lNumberOfWords_temp2=(lNumberOfWords_temp1-(lNumberOfWords_temp1 % 64))/64;
        var lNumberOfWords = (lNumberOfWords_temp2+1)*16;
        var lWordArray=new Array(lNumberOfWords-1);
        var lBytePosition = 0;
        var lByteCount = 0;
        while ( lByteCount < lMessageLength ) {
            lWordCount = (lByteCount-(lByteCount % 4))/4;
            lBytePosition = (lByteCount % 4)*8;
            lWordArray[lWordCount] = (lWordArray[lWordCount] | (str.charCodeAt(lByteCount)<<lBytePosition));
            lByteCount++;
        }
        lWordCount = (lByteCount-(lByteCount % 4))/4;
        lBytePosition = (lByteCount % 4)*8;
        lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80<<lBytePosition);
        lWordArray[lNumberOfWords-2] = lMessageLength<<3;
        lWordArray[lNumberOfWords-1] = lMessageLength>>>29;
        return lWordArray;
    };

    var wordToHex = function (lValue) {
        var wordToHexValue="",wordToHexValue_temp="",lByte,lCount;
        for (lCount = 0;lCount<=3;lCount++) {
            lByte = (lValue>>>(lCount*8)) & 255;
            wordToHexValue_temp = "0" + lByte.toString(16);
            wordToHexValue = wordToHexValue + wordToHexValue_temp.substr(wordToHexValue_temp.length-2,2);
        }
        return wordToHexValue;
    };

    var x=[],
        k,AA,BB,CC,DD,a,b,c,d,
        S11=7, S12=12, S13=17, S14=22,
        S21=5, S22=9 , S23=14, S24=20,
        S31=4, S32=11, S33=16, S34=23,
        S41=6, S42=10, S43=15, S44=21;

    str = this.utf8_encode(str);
    x = convertToWordArray(str);
    a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
    
    xl = x.length;
    for (k=0;k<xl;k+=16) {
        AA=a; BB=b; CC=c; DD=d;
        a=_FF(a,b,c,d,x[k+0], S11,0xD76AA478);
        d=_FF(d,a,b,c,x[k+1], S12,0xE8C7B756);
        c=_FF(c,d,a,b,x[k+2], S13,0x242070DB);
        b=_FF(b,c,d,a,x[k+3], S14,0xC1BDCEEE);
        a=_FF(a,b,c,d,x[k+4], S11,0xF57C0FAF);
        d=_FF(d,a,b,c,x[k+5], S12,0x4787C62A);
        c=_FF(c,d,a,b,x[k+6], S13,0xA8304613);
        b=_FF(b,c,d,a,x[k+7], S14,0xFD469501);
        a=_FF(a,b,c,d,x[k+8], S11,0x698098D8);
        d=_FF(d,a,b,c,x[k+9], S12,0x8B44F7AF);
        c=_FF(c,d,a,b,x[k+10],S13,0xFFFF5BB1);
        b=_FF(b,c,d,a,x[k+11],S14,0x895CD7BE);
        a=_FF(a,b,c,d,x[k+12],S11,0x6B901122);
        d=_FF(d,a,b,c,x[k+13],S12,0xFD987193);
        c=_FF(c,d,a,b,x[k+14],S13,0xA679438E);
        b=_FF(b,c,d,a,x[k+15],S14,0x49B40821);
        a=_GG(a,b,c,d,x[k+1], S21,0xF61E2562);
        d=_GG(d,a,b,c,x[k+6], S22,0xC040B340);
        c=_GG(c,d,a,b,x[k+11],S23,0x265E5A51);
        b=_GG(b,c,d,a,x[k+0], S24,0xE9B6C7AA);
        a=_GG(a,b,c,d,x[k+5], S21,0xD62F105D);
        d=_GG(d,a,b,c,x[k+10],S22,0x2441453);
        c=_GG(c,d,a,b,x[k+15],S23,0xD8A1E681);
        b=_GG(b,c,d,a,x[k+4], S24,0xE7D3FBC8);
        a=_GG(a,b,c,d,x[k+9], S21,0x21E1CDE6);
        d=_GG(d,a,b,c,x[k+14],S22,0xC33707D6);
        c=_GG(c,d,a,b,x[k+3], S23,0xF4D50D87);
        b=_GG(b,c,d,a,x[k+8], S24,0x455A14ED);
        a=_GG(a,b,c,d,x[k+13],S21,0xA9E3E905);
        d=_GG(d,a,b,c,x[k+2], S22,0xFCEFA3F8);
        c=_GG(c,d,a,b,x[k+7], S23,0x676F02D9);
        b=_GG(b,c,d,a,x[k+12],S24,0x8D2A4C8A);
        a=_HH(a,b,c,d,x[k+5], S31,0xFFFA3942);
        d=_HH(d,a,b,c,x[k+8], S32,0x8771F681);
        c=_HH(c,d,a,b,x[k+11],S33,0x6D9D6122);
        b=_HH(b,c,d,a,x[k+14],S34,0xFDE5380C);
        a=_HH(a,b,c,d,x[k+1], S31,0xA4BEEA44);
        d=_HH(d,a,b,c,x[k+4], S32,0x4BDECFA9);
        c=_HH(c,d,a,b,x[k+7], S33,0xF6BB4B60);
        b=_HH(b,c,d,a,x[k+10],S34,0xBEBFBC70);
        a=_HH(a,b,c,d,x[k+13],S31,0x289B7EC6);
        d=_HH(d,a,b,c,x[k+0], S32,0xEAA127FA);
        c=_HH(c,d,a,b,x[k+3], S33,0xD4EF3085);
        b=_HH(b,c,d,a,x[k+6], S34,0x4881D05);
        a=_HH(a,b,c,d,x[k+9], S31,0xD9D4D039);
        d=_HH(d,a,b,c,x[k+12],S32,0xE6DB99E5);
        c=_HH(c,d,a,b,x[k+15],S33,0x1FA27CF8);
        b=_HH(b,c,d,a,x[k+2], S34,0xC4AC5665);
        a=_II(a,b,c,d,x[k+0], S41,0xF4292244);
        d=_II(d,a,b,c,x[k+7], S42,0x432AFF97);
        c=_II(c,d,a,b,x[k+14],S43,0xAB9423A7);
        b=_II(b,c,d,a,x[k+5], S44,0xFC93A039);
        a=_II(a,b,c,d,x[k+12],S41,0x655B59C3);
        d=_II(d,a,b,c,x[k+3], S42,0x8F0CCC92);
        c=_II(c,d,a,b,x[k+10],S43,0xFFEFF47D);
        b=_II(b,c,d,a,x[k+1], S44,0x85845DD1);
        a=_II(a,b,c,d,x[k+8], S41,0x6FA87E4F);
        d=_II(d,a,b,c,x[k+15],S42,0xFE2CE6E0);
        c=_II(c,d,a,b,x[k+6], S43,0xA3014314);
        b=_II(b,c,d,a,x[k+13],S44,0x4E0811A1);
        a=_II(a,b,c,d,x[k+4], S41,0xF7537E82);
        d=_II(d,a,b,c,x[k+11],S42,0xBD3AF235);
        c=_II(c,d,a,b,x[k+2], S43,0x2AD7D2BB);
        b=_II(b,c,d,a,x[k+9], S44,0xEB86D391);
        a=addUnsigned(a,AA);
        b=addUnsigned(b,BB);
        c=addUnsigned(c,CC);
        d=addUnsigned(d,DD);
    }

    var temp = wordToHex(a)+wordToHex(b)+wordToHex(c)+wordToHex(d);

    return temp.toLowerCase();
}