var datePickerDivID = "datepicker";
		var iFrameDivID = "datepickeriframe";
		
		var dayArrayShort = new Array('Zo', 'Ma', 'Di', 'Wo', 'Do', 'Vr', 'Za');
		var dayArrayMed = new Array('Zon', 'Maa', 'Din', 'Woe', 'Don', 'Vri', 'Zat');
		var dayArrayLong = new Array('Zondag', 'Maandag', 'Dinsdag', 'Woensdag', 'Donderdag', 'Vrijdag', 'Zaterdag');
		var monthArrayShort = new Array('Jan', 'Feb', 'Mrt', 'Apr', 'Mei', 'Jun', 'Jul', 'Aug', 'Sep', 'Okt', 'Nov', 'Dec');
		var monthArrayMed = new Array('Jan', 'Feb', 'Mrt', 'Apr', 'Mei', 'Juni', 'Juli', 'Aug', 'Sept', 'Okt', 'Nov', 'Dec');
		var monthArrayLong = new Array('Januari', 'Februari', 'Maart', 'April', 'Mei', 'Juni', 'Juli', 'Augustus', 'September', 'Oktober', 'November', 'December');
		 
		// these variables define the date formatting we're expecting and outputting.
		// If you want to use a different format by default, change the defaultDateSeparator
		// and defaultDateFormat variables either here or on your HTML page.
		var defaultDateSeparator = "/";        // common values would be "/" or "."
		var defaultDateFormat = "dmy"    // valid values are "mdy", "dmy", and "ymd"
		var dateSeparator = defaultDateSeparator;
		var dateFormat = defaultDateFormat;
		
		
		function displayDatePicker(dateFieldName, displayBelowThisObject, dtFormat, dtSep)
		{
		  var targetDateField = document.getElementsByName (dateFieldName).item(0);
		 
		  // if we weren't told what node to display the datepicker beneath, just display it
		  // beneath the date field we're updating
		  if (!displayBelowThisObject)
		    displayBelowThisObject = targetDateField;
		 
		  // if a date separator character was given, update the dateSeparator variable
		  if (dtSep)
		    dateSeparator = dtSep;
		  else
		    dateSeparator = defaultDateSeparator;
		 
		  // if a date format was given, update the dateFormat variable
		  if (dtFormat)
		    dateFormat = dtFormat;
		  else
		    dateFormat = defaultDateFormat;
		 
		  var x = displayBelowThisObject.offsetLeft;
		  var y = displayBelowThisObject.offsetTop + displayBelowThisObject.offsetHeight ;
		 
		  // deal with elements inside tables and such
		  var parent = displayBelowThisObject;
		  while (parent.offsetParent) {
		    parent = parent.offsetParent;
		    x += parent.offsetLeft;
		    y += parent.offsetTop ;
		  }
		 
		  drawDatePicker(targetDateField, x, y);
		}
		
		
		
		function drawDatePicker(targetDateField, x, y)
		{
		  var dt = getFieldDate(targetDateField.value );
		 
		  // the datepicker table will be drawn inside of a <div> with an ID defined by the
		  // global datePickerDivID variable. If such a div doesn't yet exist on the HTML
		  // document we're working with, add one.
		  if (!document.getElementById(datePickerDivID)) {
		    // don't use innerHTML to update the body, because it can cause global variables
		    // that are currently pointing to objects on the page to have bad references
		    //document.body.innerHTML += "<div id='" + datePickerDivID + "' class='dpDiv'></div>";
		    var newNode = document.createElement("div");
		    newNode.setAttribute("id", datePickerDivID);
		    newNode.setAttribute("class", "dpDiv");
		    newNode.setAttribute("style", "visibility: hidden;");
		    document.body.appendChild(newNode);
		  }
		 
		  // move the datepicker div to the proper x,y coordinate and toggle the visiblity
		  var pickerDiv = document.getElementById(datePickerDivID);
		  pickerDiv.style.position = "absolute";
		  pickerDiv.style.left = x + "px";
		  pickerDiv.style.top = y + "px";
		  pickerDiv.style.visibility = (pickerDiv.style.visibility == "visible" ? "hidden" : "visible");
		  pickerDiv.style.display = (pickerDiv.style.display == "block" ? "none" : "block");
		  pickerDiv.style.zIndex = 10000;
		 
		  // draw the datepicker table
		  refreshDatePicker(targetDateField.name, dt.getFullYear(), dt.getMonth(), dt.getDate());
		}
		
		
		/**
		This is the function that actually draws the datepicker calendar.
		*/
		function refreshDatePicker(dateFieldName, year, month, day)
		{
		  // if no arguments are passed, use today's date; otherwise, month and year
		  // are required (if a day is passed, it will be highlighted later)
		  var thisDay = new Date();
		 
		  if ((month >= 0) && (year > 0)) {
		    thisDay = new Date(year, month, 1);
		  } else {
		    day = thisDay.getDate();
		    thisDay.setDate(1);
		  }
		 
		  // the calendar will be drawn as a table
		  // you can customize the table elements with a global CSS style sheet,
		  // or by hardcoding style and formatting elements below
		  var crlf = "\r\n";
		  var TABLE = "<table cols=7 class='dpTable'>" + crlf;
		  var xTABLE = "</table>" + crlf;
		  var TR = "<tr class='dpTR'>";
		  var TR_title = "<tr class='dpTitleTR'>";
		  var TR_days = "<tr class='dpDayTR'>";
		  var TR_todaybutton = "<tr class='dpTodayButtonTR'>";
		  var xTR = "</tr>" + crlf;
		  var TD = "<td class='dpTD' onMouseOut='this.className=\"dpTD\";' onMouseOver=' this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
		  var TD_title = "<td colspan=5 class='dpTitleTD'>";
		  var TD_buttons = "<td class='dpButtonTD'>";
		  var TD_todaybutton = "<td colspan=7 class='dpTodayButtonTD'>";
		  var TD_days = "<td class='dpDayTD'>";
		  var TD_selected = "<td class='dpDayHighlightTD' onMouseOut='this.className=\"dpDayHighlightTD\";' onMouseOver='this.className=\"dpTDHover\";' ";    // leave this tag open, because we'll be adding an onClick event
		  var xTD = "</td>" + crlf;
		  var DIV_title = "<div class='dpTitleText'>";
		  var DIV_selected = "<div class='dpDayHighlight'>";
		  var xDIV = "</div>";
		 
		  // start generating the code for the calendar table
		  var html = TABLE;
		 
		  // this is the title bar, which displays the month and the buttons to
		  // go back to a previous month or forward to the next month
		  html += TR_title;
		  html += TD_buttons + getButtonCode(dateFieldName, thisDay, -1, "&lt;") + xTD;
		  html += TD_title + DIV_title + monthArrayLong[ thisDay.getMonth()] + " " + thisDay.getFullYear() + xDIV + xTD;
		  html += TD_buttons + getButtonCode(dateFieldName, thisDay, 1, "&gt;") + xTD;
		  html += xTR;
		 
		  // this is the row that indicates which day of the week we're on
		  html += TR_days;
		  for(i = 0; i < dayArrayShort.length; i++)
		    html += TD_days + dayArrayShort[i] + xTD;
		  html += xTR;
		 
		  // now we'll start populating the table with days of the month
		  html += TR;
		 
		  // first, the leading blanks
		  for (i = 0; i < thisDay.getDay(); i++)
		    html += TD + "&nbsp;" + xTD;
		 
		  // now, the days of the month
		  do {
		    dayNum = thisDay.getDate();
		    TD_onclick = " onclick=\"updateDateField('" + dateFieldName + "', '" + getDateString(thisDay) + "');\">";
		    
		    if (dayNum == day)
		      html += TD_selected + TD_onclick + DIV_selected + dayNum + xDIV + xTD;
		    else
		      html += TD + TD_onclick + dayNum + xTD;
		    
		    // if this is a Saturday, start a new row
		    if (thisDay.getDay() == 6)
		      html += xTR + TR;
		    
		    // increment the day
		    thisDay.setDate(thisDay.getDate() + 1);
		  } while (thisDay.getDate() > 1)
		 
		  // fill in any trailing blanks
		  if (thisDay.getDay() > 0) {
		    for (i = 6; i > thisDay.getDay(); i--)
		      html += TD + "&nbsp;" + xTD;
		  }
		  html += xTR;
		 
		  // add a button to allow the user to easily return to today, or close the calendar
		  var today = new Date();
		  var todayString = "Today is " + dayArrayMed[today.getDay()] + ", " + monthArrayMed[ today.getMonth()] + " " + today.getDate();
		  html += TR_todaybutton + TD_todaybutton;
		  html += "<button class='dpTodayButton' onClick='refreshDatePicker(\"" + dateFieldName + "\");'>vandaag</button> ";
		  html += "<button class='dpTodayButton' onClick='updateDateField(\"" + dateFieldName + "\");'>sluiten</button>";
		  html += xTD + xTR;
		 
		  // and finally, close the table
		  html += xTABLE;
		 
		  document.getElementById(datePickerDivID).innerHTML = html;
		  // add an "iFrame shim" to allow the datepicker to display above selection lists
		  adjustiFrame();
		}
		
		
		/**
		Convenience function for writing the code for the buttons that bring us back or forward
		a month.
		*/
		function getButtonCode(dateFieldName, dateVal, adjust, label)
		{
		  var newMonth = (dateVal.getMonth () + adjust) % 12;
		  var newYear = dateVal.getFullYear() + parseInt((dateVal.getMonth() + adjust) / 12);
		  if (newMonth < 0) {
		    newMonth += 12;
		    newYear += -1;
		  }
		 
		  return "<button class='dpButton' onClick='refreshDatePicker(\"" + dateFieldName + "\", " + newYear + ", " + newMonth + ");'>" + label + "</button>";
		}
		
		
		/**
		Convert a JavaScript Date object to a string, based on the dateFormat and dateSeparator
		variables at the beginning of this script library.
		*/
		function getDateString(dateVal)
		{
		  var dayString = "00" + dateVal.getDate();
		  var monthString = "00" + (dateVal.getMonth()+1);
		  dayString = dayString.substring(dayString.length - 2);
		  monthString = monthString.substring(monthString.length - 2);
		 
		  switch (dateFormat) {
		    case "dmy" :
		      return dayString + dateSeparator + monthString + dateSeparator + dateVal.getFullYear();
		    case "ymd" :
		      return dateVal.getFullYear() + dateSeparator + monthString + dateSeparator + dayString;
		    case "mdy" :
		    default :
		      return monthString + dateSeparator + dayString + dateSeparator + dateVal.getFullYear();
		  }
		}
		
		
		/**
		Convert a string to a JavaScript Date object.
		*/
		function getFieldDate(dateString)
		{
		  var dateVal;
		  var dArray;
		  var d, m, y;
		 
		  try {
		    dArray = splitDateString(dateString);
		    if (dArray) {
		      switch (dateFormat) {
		        case "dmy" :
		          d = parseInt(dArray[0], 10);
		          m = parseInt(dArray[1], 10) - 1;
		          y = parseInt(dArray[2], 10);
		          break;
		        case "ymd" :
		          d = parseInt(dArray[2], 10);
		          m = parseInt(dArray[1], 10) - 1;
		          y = parseInt(dArray[0], 10);
		          break;
		        case "mdy" :
		        default :
		          d = parseInt(dArray[1], 10);
		          m = parseInt(dArray[0], 10) - 1;
		          y = parseInt(dArray[2], 10);
		          break;
		      }
		      dateVal = new Date(y, m, d);
		    } else if (dateString) {
		      dateVal = new Date(dateString);
		    } else {
		      dateVal = new Date();
		    }
		  } catch(e) {
		    dateVal = new Date();
		  }
		 
		  return dateVal;
		}
		
		
		/**
		Try to split a date string into an array of elements, using common date separators.
		If the date is split, an array is returned; otherwise, we just return false.
		*/
		function splitDateString(dateString)
		{
		  var dArray;
		  if (dateString.indexOf("/") >= 0)
		    dArray = dateString.split("/");
		  else if (dateString.indexOf(".") >= 0)
		    dArray = dateString.split(".");
		  else if (dateString.indexOf("-") >= 0)
		    dArray = dateString.split("-");
		  else if (dateString.indexOf("\\") >= 0)
		    dArray = dateString.split("\\");
		  else
		    dArray = false;
		 
		  return dArray;
		}
		
		
		function updateDateField(dateFieldName, dateString)
		{
		  var targetDateField = document.getElementsByName (dateFieldName).item(0);
		  if (dateString)
		    targetDateField.value = dateString;
		 
		  var pickerDiv = document.getElementById(datePickerDivID);
		  pickerDiv.style.visibility = "hidden";
		  pickerDiv.style.display = "none";
		 
		  adjustiFrame();		  
		 
		  // after the datepicker has closed, optionally run a user-defined function called
		  // datePickerClosed, passing the field that was just updated as a parameter
		  // (note that this will only run if the user actually selected a date from the datepicker)
		  if ((dateString) && (typeof(datePickerClosed) == "function"))
		    datePickerClosed(targetDateField);
		}
		
		
		
		
		/**
		Use an "iFrame shim" to deal with problems where the datepicker shows up behind
		selection list elements, if they're below the datepicker. The problem and solution are
		described at:
		
		http://dotnetjunkies.com/WebLog/jking/archive/2003/07/21/488.aspx
		http://dotnetjunkies.com/WebLog/jking/archive/2003/10/30/2975.aspx
		*/
		function adjustiFrame(pickerDiv, iFrameDiv)
		{
		  // we know that Opera doesn't like something about this, so if we
		  // think we're using Opera, don't even try
		  var is_opera = (navigator.userAgent.toLowerCase().indexOf("opera") != -1);
		  if (is_opera)
		    return;
		  
		  // put a try/catch block around the whole thing, just in case
		  try {
		    if (!document.getElementById(iFrameDivID)) {
		      // don't use innerHTML to update the body, because it can cause global variables
		      // that are currently pointing to objects on the page to have bad references
		      //document.body.innerHTML += "<iframe id='" + iFrameDivID + "' src='javascript:false;' scrolling='no' frameborder='0'>";
		      var newNode = document.createElement("iFrame");
		      newNode.setAttribute("id", iFrameDivID);
		      newNode.setAttribute("src", "javascript:false;");
		      newNode.setAttribute("scrolling", "no");
		      newNode.setAttribute ("frameborder", "0");
		      document.body.appendChild(newNode);
		    }
		    
		    if (!pickerDiv)
		      pickerDiv = document.getElementById(datePickerDivID);
		    if (!iFrameDiv)
		      iFrameDiv = document.getElementById(iFrameDivID);
		    
		    try {
		      iFrameDiv.style.position = "absolute";
		      iFrameDiv.style.width = pickerDiv.offsetWidth;
		      iFrameDiv.style.height = pickerDiv.offsetHeight ;
		      iFrameDiv.style.top = pickerDiv.style.top;
		      iFrameDiv.style.left = pickerDiv.style.left;
		      iFrameDiv.style.zIndex = pickerDiv.style.zIndex - 1;
		      iFrameDiv.style.visibility = pickerDiv.style.visibility ;
		      iFrameDiv.style.display = pickerDiv.style.display;
		    } catch(e) {
		    }
		 
		  } catch (ee) {
		  }
		 
		}