diff -Naurw moodle-clean/moodle/lib/form/dateselector.php moodle-dev/lib/form/dateselector.php
--- moodle-clean/moodle/lib/form/dateselector.php	2007-04-14 03:10:30.000000000 +0100
+++ moodle-dev/lib/form/dateselector.php	2009-02-06 10:42:24.000000000 +0000
@@ -76,9 +76,11 @@
         for ($i=$this->_options['startyear']; $i<=$this->_options['stopyear']; $i++) {
             $years[$i] = $i;
         }
-        $this->_elements[] =& MoodleQuickForm::createElement('select', 'day', get_string('day', 'form'), $days, $this->getAttributes(), true);
-        $this->_elements[] =& MoodleQuickForm::createElement('select', 'month', get_string('month', 'form'), $months, $this->getAttributes(), true);
-        $this->_elements[] =& MoodleQuickForm::createElement('select', 'year', get_string('year', 'form'), $years, $this->getAttributes(), true);
+        global$CFG;
+        $randid=rand();
+        $this->_elements[] =& MoodleQuickForm::createElement('select', 'day', get_string('day', 'form'), $days, $this->getAttributes().'id="'.$randid.'day"', true);
+        $this->_elements[] =& MoodleQuickForm::createElement('select', 'month', get_string('month', 'form'), $months, $this->getAttributes().'id="'.$randid.'month" onChange="WeekDays('.$randid.')"', true);
+        $this->_elements[] =& MoodleQuickForm::createElement('select', 'year', get_string('year', 'form'), $years, $this->getAttributes().'id="'.$randid.'year" onChange="WeekDays('.$randid.')"', true);
         // If optional we add a checkbox which the user can use to turn if on
         if($this->_options['optional']) {
             $this->_elements[] =& MoodleQuickForm::createElement('checkbox', 'off', null, get_string('disable'), $this->getAttributes(), true);
@@ -88,6 +90,9 @@
                 $element->setHiddenLabel(true);
             }
         }
+        require_js('yui_yahoo');
+        require_js('yui_event');
+        require_js($CFG->wwwroot.'/lib/form/weekdays.js.php');
 
     }
 
diff -Naurw moodle-clean/moodle/lib/form/datetimeselector.php moodle-dev/lib/form/datetimeselector.php
--- moodle-clean/moodle/lib/form/datetimeselector.php	2007-08-09 17:56:36.000000000 +0100
+++ moodle-dev/lib/form/datetimeselector.php	2009-02-06 10:42:28.000000000 +0000
@@ -81,9 +81,11 @@
         for ($i=0; $i<60; $i+=$this->_options['step']) {
             $minutes[$i] = sprintf("%02d",$i);
         }
-        $this->_elements[] =& MoodleQuickForm::createElement('select', 'day', get_string('day', 'form'), $days, $this->getAttributes(), true);
-        $this->_elements[] =& MoodleQuickForm::createElement('select', 'month', get_string('month', 'form'), $months, $this->getAttributes(), true);
-        $this->_elements[] =& MoodleQuickForm::createElement('select', 'year', get_string('year', 'form'), $years, $this->getAttributes(), true);
+        global$CFG;
+        $randid=rand();
+        $this->_elements[] =& MoodleQuickForm::createElement('select', 'day', get_string('day', 'form'), $days, $this->getAttributes().'id="'.$randid.'day"', true);
+        $this->_elements[] =& MoodleQuickForm::createElement('select', 'month', get_string('month', 'form'), $months, $this->getAttributes().'id="'.$randid.'month" onChange="WeekDays('.$randid.')"', true);
+        $this->_elements[] =& MoodleQuickForm::createElement('select', 'year', get_string('year', 'form'), $years, $this->getAttributes().'id="'.$randid.'year" onChange="WeekDays('.$randid.')"', true);
 		if (right_to_left()) {   // Switch order of elements for Right-to-Left
 			$this->_elements[] =& MoodleQuickForm::createElement('select', 'minute', get_string('minute', 'form'), $minutes, $this->getAttributes(), true);
 			$this->_elements[] =& MoodleQuickForm::createElement('select', 'hour', get_string('hour', 'form'), $hours, $this->getAttributes(), true);
@@ -100,6 +102,9 @@
                 $element->setHiddenLabel(true);
             }
         }
+        require_js('yui_yahoo');
+        require_js('yui_event');
+        require_js($CFG->wwwroot.'/lib/form/weekdays.js.php');
 
     }
 
diff -Naurw moodle-clean/moodle/lib/form/weekdays.js.php moodle-dev/lib/form/weekdays.js.php
--- moodle-clean/moodle/lib/form/weekdays.js.php	1970-01-01 01:00:00.000000000 +0100
+++ moodle-dev/lib/form/weekdays.js.php	2009-02-06 10:50:45.000000000 +0000
@@ -0,0 +1,54 @@
+function WeekDays(randid){
+	DaysObject=document.getElementById(randid+"day");
+	MonthObject=document.getElementById(randid+"month");
+	YearObject=document.getElementById(randid+"year");
+
+	month=(MonthObject.selectedIndex +1);
+	year=YearObject.options[YearObject.selectedIndex].value;
+<?php
+	require_once("../../config.php");
+    echo'var week=new Array(7);
+    week[1]="'.get_string('mon','calendar').'";
+    week[2]="'.get_string('tue','calendar').'";
+    week[3]="'.get_string('wed','calendar').'";
+    week[4]="'.get_string('thu','calendar').'";
+    week[5]="'.get_string('fri','calendar').'";
+    week[6]="'.get_string('sat','calendar').'";
+    week[0]="'.get_string('sun','calendar').'";';
+?>
+    var day=DaysObject.selectedIndex+1;
+    var currentDay = DaysObject.selectedIndex;
+    var month=MonthObject.selectedIndex;
+    var year=YearObject.options[YearObject.selectedIndex].value;
+   
+    //wipe current list
+    for (j = DaysObject.options.length; j >= 0; j--) {
+        DaysObject.options[j] = null;
+    }
+    
+    var i=new Date();
+    i.setDate(1);
+    i.setMonth(month);
+    i.setYear(year);
+    
+    while (i.getMonth()==month){
+        
+      DaysObject.options[i.getDate()-1] = new Option(week[i.getDay()]+" "+i.getDate(),i.getDate());
+      i.setTime(i.getTime() + 86400000);
+    }
+   DaysObject.selectedIndex = currentDay;
+
+   
+   
+}
+function WeekDaysInit(){
+	allFieldsets=document.getElementsByTagName("fieldset"); 
+    for (i = allFieldsets.length-1; i >= 0; i--) {
+    	if((allFieldsets[i].className.indexOf('fdate_time_selector')!=-1)||(allFieldsets[i].className.indexOf('fdate_selector')!=-1)){
+    		randId=allFieldsets[i].childNodes[1].id.substr(0,allFieldsets[i].childNodes[1].id.length-3);
+    		WeekDays(randId);
+    	}
+    }
+
+}
+YAHOO.util.Event.onDOMReady(WeekDaysInit);