function arrayExists(array, x) {

    for (var i = 0; i < array.length; i++) {

        if (array[i] == x) return true;

    }

    return false;

}

Date.prototype.formatDate = function (input,time) {

    // formatDate :

    // a PHP date like function, for formatting date strings

    // See: http://www.php.net/date

    //

    // input : format string

    // time : epoch time (seconds, and optional)

    //

    // if time is not passed, formatting is based on 

    // the current "this" date object's set time.

    //

    // supported:

    // a, A, B, d, D, F, g, G, h, H, i, j, l (lowercase L), L, 

    // m, M, n, O, r, s, S, t, U, w, W, y, Y, z

    //

    // unsupported:

    // I (capital i), T, Z    

    var switches =    ["a", "A", "B", "d", "D", "F", "g", "G", "h", "H", 

                       "i", "j", "l", "L", "m", "M", "n", "O", "r", "s", 

                       "S", "t", "U", "w", "W", "y", "Y", "z"];

    var daysLong =    ["Sunday", "Monday", "Tuesday", "Wednesday", 

                       "Thursday", "Friday", "Saturday"];

    var daysShort =   ["Sun", "Mon", "Tue", "Wed", 

                       "Thu", "Fri", "Sat"];

    var monthsShort = ["Jan", "Feb", "Mar", "Apr",

                       "May", "Jun", "Jul", "Aug", "Sep",

                       "Oct", "Nov", "Dec"];

    var monthsLong =  ["January", "February", "March", "April",

                       "May", "June", "July", "August", "September",

                       "October", "November", "December"];

    var daysSuffix = ["st", "nd", "rd", "th", "th", "th", "th", // 1st - 7th

                      "th", "th", "th", "th", "th", "th", "th", // 8th - 14th

                      "th", "th", "th", "th", "th", "th", "st", // 15th - 21st

                      "nd", "rd", "th", "th", "th", "th", "th", // 22nd - 28th

                      "th", "th", "st"];                        // 29th - 31st

    function a() {

        // Lowercase Ante meridiem and Post meridiem

        return self.getHours() > 11? "pm" : "am";

    }

    function A() {

        // Uppercase Ante meridiem and Post meridiem

        return self.getHours() > 11? "PM" : "AM";

    }

    function B(){

        // Swatch internet time. code simply grabbed from ppk,

        // since I was feeling lazy:

        // http://www.xs4all.nl/~ppk/js/beat.html

        var off = (self.getTimezoneOffset() + 60)*60;

        var theSeconds = (self.getHours() * 3600) + 

                         (self.getMinutes() * 60) + 

                          self.getSeconds() + off;

        var beat = Math.floor(theSeconds/86.4);

        if (beat > 1000) beat -= 1000;

        if (beat < 0) beat += 1000;

        if ((""+beat).length == 1) beat = "00"+beat;

        if ((""+beat).length == 2) beat = "0"+beat;

        return beat;

    }

    function d() {

        // Day of the month, 2 digits with leading zeros

        return new String(self.getDate()).length == 1?

        "0"+self.getDate() : self.getDate();

    }

    function D() {

        // A textual representation of a day, three letters

        return daysShort[self.getDay()];

    }

    function F() {

        // A full textual representation of a month

        return monthsLong[self.getMonth()];

    }

    function g() {

        // 12-hour format of an hour without leading zeros

        return self.getHours() > 12? self.getHours()-12 : self.getHours();

    }

    function G() {

        // 24-hour format of an hour without leading zeros

        return self.getHours();

    }

    function h() {

        // 12-hour format of an hour with leading zeros

        if (self.getHours() > 12) {

          var s = new String(self.getHours()-12);

          return s.length == 1?

          "0"+ (self.getHours()-12) : self.getHours()-12;

        } else { 

          var s = new String(self.getHours());

          return s.length == 1?

          "0"+self.getHours() : self.getHours();

        }  

    }

    function H() {

        // 24-hour format of an hour with leading zeros

        return new String(self.getHours()).length == 1?

        "0"+self.getHours() : self.getHours();

    }

    function i() {

        // Minutes with leading zeros

        return new String(self.getMinutes()).length == 1? 

        "0"+self.getMinutes() : self.getMinutes(); 

    }

    function j() {

        // Day of the month without leading zeros

        return self.getDate();

    }    

    function l() {

        // A full textual representation of the day of the week

        return daysLong[self.getDay()];

    }

    function L() {

        // leap year or not. 1 if leap year, 0 if not.

        // the logic should match iso's 8601 standard.

        var y_ = Y();

        if (         

            (y_ % 4 == 0 && y_ % 100 != 0) ||

            (y_ % 4 == 0 && y_ % 100 == 0 && y_ % 400 == 0)

            ) {

            return 1;

        } else {

            return 0;

        }

    }

    function m() {

        // Numeric representation of a month, with leading zeros

        return self.getMonth() < 9?

        "0"+(self.getMonth()+1) : 

        self.getMonth()+1;

    }

    function M() {

        // A short textual representation of a month, three letters

        return monthsShort[self.getMonth()];

    }

    function n() {

        // Numeric representation of a month, without leading zeros

        return self.getMonth()+1;

    }

    function O() {

        // Difference to Greenwich time (GMT) in hours

        var os = Math.abs(self.getTimezoneOffset());

        var h = ""+Math.floor(os/60);

        var m = ""+(os%60);

        h.length == 1? h = "0"+h:1;

        m.length == 1? m = "0"+m:1;

        return self.getTimezoneOffset() < 0 ? "+"+h+m : "-"+h+m;

    }

    function r() {

        // RFC 822 formatted date

        var r; // result

        //  Thu    ,     21          Dec         2000

        r = D() + ", " + j() + " " + M() + " " + Y() +

        //        16     :    01     :    07          +0200

            " " + H() + ":" + i() + ":" + s() + " " + O();

        return r;

    }

    function S() {

        // English ordinal suffix for the day of the month, 2 characters

        return daysSuffix[self.getDate()-1];

    }

    function s() {

        // Seconds, with leading zeros

        return new String(self.getSeconds()).length == 1?

        "0"+self.getSeconds() : self.getSeconds();

    }

    function t() {

        // thanks to Matt Bannon for some much needed code-fixes here!

        var daysinmonths = [null,31,28,31,30,31,30,31,31,30,31,30,31];

        if (L()==1 && n()==2) return 29; // leap day

        return daysinmonths[n()];

    }

    function U() {

        // Seconds since the Unix Epoch (January 1 1970 00:00:00 GMT)

        return Math.round(self.getTime()/1000);

    }

    function W() {

        // Weeknumber, as per ISO specification:

        // http://www.cl.cam.ac.uk/~mgk25/iso-time.html

        // if the day is three days before newyears eve,

        // there's a chance it's "week 1" of next year.

        // here we check for that.

        var beforeNY = 364+L() - z();

        var afterNY  = z();

        var weekday = w()!=0?w()-1:6; // makes sunday (0), into 6.

        if (beforeNY <= 2 && weekday <= 2-beforeNY) {

            return 1;

        }

        // similarly, if the day is within threedays of newyears

        // there's a chance it belongs in the old year.

        var ny = new Date("January 1 " + Y() + " 00:00:00");

        var nyDay = ny.getDay()!=0?ny.getDay()-1:6;

        if (

            (afterNY <= 2) && 

            (nyDay >=4)  && 

            (afterNY >= (6-nyDay))

            ) {

            // Since I'm not sure we can just always return 53,

            // i call the function here again, using the last day

            // of the previous year, as the date, and then just

            // return that week.

            var prevNY = new Date("December 31 " + (Y()-1) + " 00:00:00");

            return prevNY.formatDate("W");

        }

        // week 1, is the week that has the first thursday in it.

        // note that this value is not zero index.

        if (nyDay <= 3) {

            // first day of the year fell on a thursday, or earlier.

            return 1 + Math.floor( ( z() + nyDay ) / 7 );

        } else {

            // first day of the year fell on a friday, or later.

            return 1 + Math.floor( ( z() - ( 7 - nyDay ) ) / 7 );

        }

    }

    function w() {

        // Numeric representation of the day of the week

        return self.getDay();

    }

    function Y() {

        // A full numeric representation of a year, 4 digits

        // we first check, if getFullYear is supported. if it

        // is, we just use that. ppks code is nice, but wont

        // work with dates outside 1900-2038, or something like that

        if (self.getFullYear) {

            var newDate = new Date("January 1 2001 00:00:00 +0000");

            var x = newDate .getFullYear();

            if (x == 2001) {              

                // i trust the method now

                return self.getFullYear();

            }

        }

        // else, do this:

        // codes thanks to ppk:

        // http://www.xs4all.nl/~ppk/js/introdate.html

        var x = self.getYear();

        var y = x % 100;

        y += (y < 38) ? 2000 : 1900;

        return y;

    }

    function y() {

        // A two-digit representation of a year

        var y = Y()+"";

        return y.substring(y.length-2,y.length);

    }

    function z() {

        // The day of the year, zero indexed! 0 through 366

        var t = new Date("January 1 " + Y() + " 00:00:00");

        var diff = self.getTime() - t.getTime();

        return Math.floor(diff/1000/60/60/24);

    }

    var self = this;

    if (time) {

        // save time

        var prevTime = self.getTime();

        self.setTime(time);

    }

    var ia = input.split("");

    var ij = 0;

    while (ia[ij]) {

        if (ia[ij] == "\\") {

            // this is our way of allowing users to escape stuff

            ia.splice(ij,1);

        } else {

            if (arrayExists(switches,ia[ij])) {

                ia[ij] = eval(ia[ij] + "()");

            }

        }

        ij++;

    }

    // reset time, back to what it was

    if (prevTime) {

        self.setTime(prevTime);

    }

    return ia.join("");

}

var date = new Date("1/1/2007 1:11:11");

for (i = 0; i < 500; ++i) {

    var shortFormat = date.formatDate("Y-m-d");

    var longFormat = date.formatDate("l, F d, Y g:i:s A");

    date.setTime(date.getTime() + 84266956);

}