diff --git a/main/attendance/attendance_add.php b/main/attendance/attendance_add.php
index dda715d2f1..6c6b5086de 100755
--- a/main/attendance/attendance_add.php
+++ b/main/attendance/attendance_add.php
@@ -31,8 +31,8 @@ $form->applyFilter('title','html_filter');
 $form->add_html_editor('description', get_lang('Description'), false, false, array('ToolbarSet' => 'TrainingDescription', 'Width' => '100%', 'Height' => '200'));
 
 // Adavanced Parameters
-$form->addElement('html', '<div class="row"><div class="label">');
-$form->addElement('html', '<div class="formw"><a href="javascript://" class = "advanced_parameters" ><span id="img_plus_and_minus">&nbsp;'.Display::return_icon('div_show.gif',get_lang('Show'),array('style'=>'vertical-align:middle')).' '.get_lang('AdvancedParameters').'</span></a></div></div></div>');
+$form->addElement('html', '<div class="row"><div class="label"></div>');
+$form->addElement('html', '<div class="formw"><br /><a href="javascript://" class = "advanced_parameters" ><span id="img_plus_and_minus">&nbsp;'.Display::return_icon('div_show.gif',get_lang('Show'),array('style'=>'vertical-align:middle')).' '.get_lang('AdvancedParameters').'</span></a></div></div>');
 $form->addElement('html','<div id="id_qualify" style="display:none">');
 
 // Qualify Attendance for gradebook option
diff --git a/main/attendance/attendance_controller.php b/main/attendance/attendance_controller.php
index 26b081f600..61f58b1b46 100755
--- a/main/attendance/attendance_controller.php
+++ b/main/attendance/attendance_controller.php
@@ -179,38 +179,17 @@
 		$data['next_attendance_calendar_id'] = $attendance->get_next_attendance_calendar_id($attendance_id);
 		
 		if (strtoupper($_SERVER['REQUEST_METHOD']) == "POST") {	
-			$presences = array();
-			$check_values = array();
-			$users_present = array();
 
-			if (isset($_POST['check_presence'])) {
-				$presences = $_POST['check_presence'];
-				$calendar_tmp = array();
-				foreach ($presences as $presence) {						
-					$presence_split = explode('_',$presence);
-					$calendar_id = $presence_split[1];
-					$user_id = $presence_split[3];
-					$calendar_tmp[] = $calendar_id;					
-					if (in_array($calendar_id, $calendar_tmp)) {
-						$check_values[$calendar_id][] = $user_id;		
+			if (isset($_POST['hidden_input'])) {
+				foreach ($_POST['hidden_input'] as $cal_id) {
+					$users_present = array();
+					if (isset($_POST['check_presence'][$cal_id])) {
+						$users_present = $_POST['check_presence'][$cal_id];
 					}
+					$affected_rows = $attendance->attendance_sheet_add($cal_id,$users_present,$attendance_id);					
 				}
-				// save when is present at least one user
-				foreach ($check_values as $cal_id => $value) {
-					$users_present = $value;				
-					$affected_rows = $attendance->attendance_sheet_add($cal_id,$users_present,$attendance_id);								
-				}
-								
-			} else {
-				// save attendance done with all absents students				
-				if (isset($_POST['datetime_column'])) {
-					foreach ($_POST['datetime_column'] as $key=>$date_time_col) {
-						$cal_id = $key;
-						$affected_rows = $attendance->attendance_sheet_add($cal_id,$users_present,$attendance_id);
-					}	
-				}
-			}		
-					
+			}
+
 			$data['users_in_course'] = $attendance->get_users_rel_course($attendance_id);
 			$data['attendant_calendar'] = $attendance->get_attendance_calendar($attendance_id);
 			$data['users_presence'] = $attendance->get_users_attendance_sheet($attendance_id);
diff --git a/main/attendance/attendance_edit.php b/main/attendance/attendance_edit.php
index 7a75894b21..393876477a 100755
--- a/main/attendance/attendance_edit.php
+++ b/main/attendance/attendance_edit.php
@@ -33,14 +33,14 @@ $form->applyFilter('title','html_filter');
 $form->add_html_editor('description', get_lang('Description'), false, false, array('ToolbarSet' => 'TrainingDescription', 'Width' => '100%', 'Height' => '200'));
 
 // Adavanced Parameters
-$form->addElement('html', '<div class="row"><div class="label">');
+$form->addElement('html', '<div class="row"><div class="label"></div>');
 if (!empty($attendance_qualify_title) || !empty($attendance_weight)) {
-	$form->addElement('html', '<div class="formw"><a href="javascript://" class="advanced_parameters"><span id="img_plus_and_minus">&nbsp;'.Display::return_icon('div_hide.gif',get_lang('Show'),array('style'=>'vertical-align:middle')).' '.get_lang('AdvancedParameters').'</span></a></div></div></div>');
+	$form->addElement('html', '<div class="formw"><br /><a href="javascript://" class="advanced_parameters"><span id="img_plus_and_minus">&nbsp;'.Display::return_icon('div_hide.gif',get_lang('Show'),array('style'=>'vertical-align:middle')).' '.get_lang('AdvancedParameters').'</span></a></div></div>');
 	$form->addElement('html','<div id="id_qualify" style="display:block">');
 	$form->addElement('checkbox', 'attendance_qualify_gradebook', '', get_lang('QualifyAttendanceGradebook'),array('checked'=>'true','onclick'=>'javascript:if(this.checked==true){document.getElementById(\'options_field\').style.display = \'block\';}else{document.getElementById(\'options_field\').style.display = \'none\';}'));
 	$form -> addElement('html','<div id="options_field" style="display:block">');
 } else {
-	$form->addElement('html', '<div class="formw"><a href="javascript://" class="advanced_parameters"><span id="img_plus_and_minus">&nbsp;'.Display::return_icon('div_show.gif',get_lang('Show'),array('style'=>'vertical-align:middle')).' '.get_lang('AdvancedParameters').'</span></a></div></div></div>');
+	$form->addElement('html', '<div class="formw"><br /><a href="javascript://" class="advanced_parameters"><span id="img_plus_and_minus">&nbsp;'.Display::return_icon('div_show.gif',get_lang('Show'),array('style'=>'vertical-align:middle')).' '.get_lang('AdvancedParameters').'</span></a></div></div>');
 	$form->addElement('html','<div id="id_qualify" style="display:none">');
 	$form->addElement('checkbox', 'attendance_qualify_gradebook', '', get_lang('QualifyAttendanceGradebook'),'onclick="javascript:if(this.checked==true){document.getElementById(\'options_field\').style.display = \'block\';}else{document.getElementById(\'options_field\').style.display = \'none\';}"');
 	$form -> addElement('html','<div id="options_field" style="display:none">');
diff --git a/main/attendance/attendance_sheet.php b/main/attendance/attendance_sheet.php
index 97a3f914e5..b3a7469965 100755
--- a/main/attendance/attendance_sheet.php
+++ b/main/attendance/attendance_sheet.php
@@ -34,7 +34,7 @@ if (api_is_allowed_to_edit(null, true)) {
 	
 			<table class="data_table" width="100%">
 				<tr class="row_odd" >	
-					<th height="60px" width="35px" ><?php echo get_lang('Order')?></th>
+					<th height="65px" width="35px" ><?php echo get_lang('Order')?></th>
 					<th width="45px" ><?php echo get_lang('Photo')?></th>
 					<th><?php echo get_lang('LastName')?></th>
 					<th><?php echo get_lang('FirstName')?></th>
@@ -70,22 +70,27 @@ if (api_is_allowed_to_edit(null, true)) {
 				<?php			
 					if (count($attendant_calendar) > 0 ) {
 						foreach ($attendant_calendar as $calendar) {												
-							//$datetime = explode(' ',$calendar['date_time']);
+
 							$date = $calendar['date'];
 							$time = $calendar['time'];
 							$datetime = $date.'<br />'.$time;
-							$checked_date = '';						
+														
+							$img_lock = Display::return_icon('lock.gif',get_lang('DateLock'),array('class'=>'img_lock','id'=>'datetime_column_'.$calendar['id']));													
 							if (!empty($calendar['done_attendance'])){
 								$datetime = '<font color="blue">'.$date.'<br />'.$time.'</font>';
-							}						
+							}
+							$disabled_check = 'disabled';
+							$input_hidden = '<input type="hidden" id="hidden_input_'.$calendar['id'].'" name="hidden_input[]" value="" disabled />';						
 							if ($next_attendance_calendar_id == $calendar['id']) {
-								$checked_date = 'checked';
-							}													
-					?>
-							<th height="60px" style="padding:5px;"><?php echo '<span style="font-size:10px;">'.$datetime.'<br /><input type="checkbox" name="datetime_column['.$calendar['id'].']" id="datetime_column_'.$calendar['id'].'" '.$checked_date.'/></span>' ?></th>
+								$input_hidden = '<input type="hidden" id="hidden_input_'.$calendar['id'].'" name="hidden_input[]" value="'.$calendar['id'].'" />';
+								$disabled_check = '';
+								$img_lock = Display::return_icon('unlock.gif',get_lang('DateUnlock'),array('class'=>'img_unlock','id'=>'datetime_column_'.$calendar['id']));
+							}										
+					?>							
+							<th height="65px" style="padding:1px 5px;" ><?php echo '<center><div style="font-size:10px;min-width:80px;width:80px;">'.$datetime.'&nbsp;<span id="attendance_lock" style="cursor:pointer">'.$img_lock.'</span><br /><input type="checkbox" id="checkbox_head_'.$calendar['id'].'" '.$disabled_check.' checked />'.$input_hidden.'</div></center>' ?></th>
 					<?php }					
 					} else { ?>
-						<th height="60px" style="padding:5px;"><span><a href="index.php?<?php echo api_get_cidreq() ?>&action=calendar_list&attendance_id=<?php echo $attendance_id.$param_gradebook ?>">
+						<th height="65px" style="padding:5px;"><span><a href="index.php?<?php echo api_get_cidreq() ?>&action=calendar_list&attendance_id=<?php echo $attendance_id.$param_gradebook ?>">
 						<?php echo Display::return_icon('calendar_up.gif',get_lang('AttendanceCalendar')).' '.get_lang('GoToAttendanceCalendar') ?></a></span></th>
 					<?php } ?>
 				</tr>			
@@ -116,7 +121,7 @@ if (api_is_allowed_to_edit(null, true)) {
 									$disabled = '';
 								}
 					?>
-							<td height="50px" style="<?php echo $style_td ?>" class="checkboxes_col_<?php echo $calendar['id'] ?>"><center><input type="checkbox" name="check_presence[]" value="cal_<?php echo $calendar['id'] ?>_user_<?php echo $user['user_id'] ?>"  <?php echo $disabled.' '.$checked ?> /><span class="<?php echo 'anchor_'.$calendar['id'] ?>"></span></center></td>
+							<td height="50px" style="<?php echo $style_td ?>" class="checkboxes_col_<?php echo $calendar['id'] ?>"><center><input type="checkbox" name="check_presence[<?php echo $calendar['id'] ?>][]" value="<?php echo $user['user_id'] ?>"  <?php echo $disabled.' '.$checked ?> /><span class="<?php echo 'anchor_'.$calendar['id'] ?>"></span></center></td>
 							
 					<?php 	} 
 						} else { ?>
@@ -143,13 +148,15 @@ if (api_is_allowed_to_edit(null, true)) {
 	// View for students
 ?>	
 	<h3><?php echo get_lang('AttendanceSheetReport') ?></h3>
-	<div>
-		<table width="200px;">
-		<tr>
-			<td><?php echo get_lang('Faults').': ' ?></td><td><center><div class="attendance-faults-bar" style="background-color:<?php echo (!empty($faults['color_bar'])?$faults['color_bar']:'none') ?>"><?php echo $faults['faults'].'/'.$faults['total'].' ('.$faults['faults_porcent'].'%)' ?></div></center></td>
-		</tr>	
-		</table>
-	</div>
+	<?php if(!empty($users_presence)) { ?>
+		<div>
+			<table width="200px;">
+			<tr>
+				<td><?php echo get_lang('Faults').': ' ?></td><td><center><div class="attendance-faults-bar" style="background-color:<?php echo (!empty($faults['color_bar'])?$faults['color_bar']:'none') ?>"><?php echo $faults['faults'].'/'.$faults['total'].' ('.$faults['faults_porcent'].'%)' ?></div></center></td>
+			</tr>	
+			</table>
+		</div>
+	<?php } ?>
 	<div>
 	<br />
 	<center>
@@ -159,15 +166,21 @@ if (api_is_allowed_to_edit(null, true)) {
 					<th><?php echo get_lang('Attendance')?></th>				
 				</tr>
 				<?php 
-				$i = 0;
-				foreach($users_presence[$user_id] as $presence) { 
-					$class = '';
-					if ($i%2==0) {$class = 'row_even';}
-					else {$class = 'row_odd';}	
+				
+				if (!empty($users_presence)) {
+					$i = 0;
+					foreach($users_presence[$user_id] as $presence) { 
+						$class = '';
+						if ($i%2==0) {$class = 'row_even';}
+						else {$class = 'row_odd';}	
+					?>
+					<tr class="<?php echo $class ?>"><td><?php echo Display::return_icon('lp_calendar_event.png',get_lang('DateTime')).' '.$presence['date_time'] ?></td><td><center><?php echo $presence['presence']?Display::return_icon('checkbox_on.gif',get_lang('Presence')):Display::return_icon('checkbox_off.gif',get_lang('Presence')) ?></center></td></tr>					
+				<?php } 
+				} else { ?>
+				<tr><td colspan="2"><center><?php echo get_lang('YouDoNotHaveDoneAttendance')?></center></td></tr>	
+				<?php }
+				
 				?>
-				<tr class="<?php echo $class ?>"><td><?php echo Display::return_icon('lp_calendar_event.png',get_lang('DateTime')).' '.$presence['date_time'] ?></td><td><center><?php echo $presence['presence']?Display::return_icon('checkbox_on.gif',get_lang('Presence')):Display::return_icon('checkbox_off.gif',get_lang('Presence')) ?></center></td></tr>	
-					
-				<?php } ?>
 		</table>			
 	</center>
 	</div>
diff --git a/main/attendance/index.php b/main/attendance/index.php
index cb787fdf92..add8b61236 100644
--- a/main/attendance/index.php
+++ b/main/attendance/index.php
@@ -66,17 +66,45 @@ $htmlHeadXtra[] = '<link rel="stylesheet" href="'.api_get_path(WEB_LIBRARY_PATH)
 $htmlHeadXtra[] = '<script language="javascript">
 		
 			$(function() {	
-				$("table th input:checkbox").click(function() {
+									
+				$("table th img").click(function() {
+					
 					var col_id = this.id;
 					var col_split = col_id.split("_");							
 					var calendar_id = col_split[2];
-					if ($("#"+col_id).is(":checked")) {
-						$(".checkboxes_col_"+calendar_id).css({"background-color":"#e1e1e1"});
-						$(".checkboxes_col_"+calendar_id+" input:checkbox").attr("disabled",false);
-					} else {
+					var class_img = $(this).attr("class");
+					
+					if (class_img == "img_unlock") {
+						$("#checkbox_head_"+calendar_id).attr("disabled",true);
 						$(".row_odd td.checkboxes_col_"+calendar_id).css({"background-color":"#F2F2F2"});
 						$(".row_even td.checkboxes_col_"+calendar_id).css({"background-color":"#FFF"});
-						$(".checkboxes_col_"+calendar_id+" input:checkbox").attr("disabled",true);
+						$(".checkboxes_col_"+calendar_id+" input:checkbox").attr("disabled",true);							 						
+						$(this).attr("src","'.api_get_path(WEB_CODE_PATH).'img/lock.gif");
+						$(this).attr("class","img_lock");
+						$("#hidden_input_"+calendar_id).attr("value","");
+						$("#hidden_input_"+calendar_id).attr("disabled",true);
+						return false;
+					} else {
+						$("#checkbox_head_"+calendar_id).attr("disabled",false);
+						$(".checkboxes_col_"+calendar_id).css({"background-color":"#e1e1e1"});
+						$(".checkboxes_col_"+calendar_id+" input:checkbox").attr("disabled",false);						
+						$(this).attr("src","'.api_get_path(WEB_CODE_PATH).'img/unlock.gif");
+						$(this).attr("class","img_unlock");												
+						$("#hidden_input_"+calendar_id).attr("disabled",false);
+						$("#hidden_input_"+calendar_id).attr("value",calendar_id);						
+						return false;
+					}	
+					
+				});	
+				
+				$("table th input:checkbox").click(function() {
+					var col_id = this.id;
+					var col_split = col_id.split("_");							
+					var calendar_id = col_split[2];
+					if ($("#"+col_id).is(":checked")) {
+						$(".checkboxes_col_"+calendar_id+" input:checkbox").attr("checked",true);
+					} else {						
+						$(".checkboxes_col_"+calendar_id+" input:checkbox").attr("checked",false);
 					}
 				});
 					
diff --git a/main/inc/lib/attendance.lib.php b/main/inc/lib/attendance.lib.php
index 5806dca779..2a3a34bc1c 100755
--- a/main/inc/lib/attendance.lib.php
+++ b/main/inc/lib/attendance.lib.php
@@ -2,7 +2,7 @@
 /* For licensing terms, see /license.txt */
 
 /**
- * This file contains class used like library provides functions for attendance tool. It's also used like model to attendance_controller (MVC pattern)
+ * This file contains class used like library, provides functions for attendance tool. It's also used like model to attendance_controller (MVC pattern)
  * @author Christian Fasanando <christian1827@gmail.com>
  * @package chamilo.attendance
  */
@@ -779,7 +779,7 @@ class Attendance
 
 	/**
 	 * buid a string datetime from array
-	 * @param	array	array containing data e.g: e.g: $array('Y'=>'2010',  'F' => '02', 'd' => '10', 'H' => '12', 'i' => '30')
+	 * @param	array	array containing data e.g: $array('Y'=>'2010',  'F' => '02', 'd' => '10', 'H' => '12', 'i' => '30')
 	 * @return	string	date and time e.g: '2010-02-10 12:30:00'
 	 */
 	public function build_datetime_from_array($array) {