diff --git a/documentation/changelog.html b/documentation/changelog.html
index 6013ee0817..d8f9297125 100644
--- a/documentation/changelog.html
+++ b/documentation/changelog.html
@@ -165,6 +165,7 @@
   <li>Fixed a bug in migration for several versions at once whereby new course tools were repeated several times (SVN#17935)</li>
   <li>Fixed security issue allowing users to upload php files on the server through FCKEditor (FS#2970)</li> 
   <li>Fixed folders by default into document tool must not be removed - see FS#3611</li>
+  <li>Fixed qualification of themes into forum tool - see FS#3609</li>
 </ul>
 <br />
 <h3>CSS changes</h3>
diff --git a/main/forum/editpost.php b/main/forum/editpost.php
index 5effe99a51..9e162c3b3b 100644
--- a/main/forum/editpost.php
+++ b/main/forum/editpost.php
@@ -102,6 +102,20 @@ $nameTools=get_lang('Forum');
 */
 include('forumconfig.inc.php');
 include('forumfunction.inc.php');
+
+// javascript
+$htmlHeadXtra[] = '<script>
+		
+		function advanced_parameters() {
+			if(document.getElementById(\'id_qualify\').style.display == \'none\') {
+				document.getElementById(\'id_qualify\').style.display = \'block\';
+				document.getElementById(\'img_plus_and_minus\').innerHTML=\'&nbsp;<img src="../img/nolines_minus.gif" alt="" />&nbsp;'.get_lang('AdvancedParameters').'\';
+			} else {
+				document.getElementById(\'id_qualify\').style.display = \'none\';
+				document.getElementById(\'img_plus_and_minus\').innerHTML=\'&nbsp;<img src="../img/nolines_plus.gif" alt="" />&nbsp;'.get_lang('AdvancedParameters').'\';
+			}	
+		}
+</script>';	
 
 /*
 ==============================================================================
diff --git a/main/forum/forumbody.inc.php b/main/forum/forumbody.inc.php
index a25673c27b..b512633a58 100644
--- a/main/forum/forumbody.inc.php
+++ b/main/forum/forumbody.inc.php
@@ -63,7 +63,7 @@ $output .= '
         <tr>
             <td width="40%" class="forum-thread-header"><div align="left">'.get_lang('Qualification').'&nbsp;:</div></td >
             <td  width="60%" class="forum-thread-body"><div align="left">
-            	<input type="text" maxlength="4" id="idtextqualify" style="width:40px;" name="idtextqualify" value="'.$my_idtextqualify.'" />&nbsp;&nbsp;'.get_lang('MaxScore').'&nbsp;: '.$max_qualify.'</div>
+            	<input type="text" maxlength="8" id="idtextqualify" style="width:60px;" name="idtextqualify" value="'.$my_idtextqualify.'" />&nbsp;&nbsp;'.get_lang('MaxScore').'&nbsp;: '.$max_qualify.'</div>
             </td>
         </tr>
     	<tr>
diff --git a/main/forum/forumfunction.inc.php b/main/forum/forumfunction.inc.php
index 9fd17b43da..ae59464ec7 100644
--- a/main/forum/forumfunction.inc.php
+++ b/main/forum/forumfunction.inc.php
@@ -1876,14 +1876,17 @@ function show_add_post_form($action='', $id='', $form_values='') {
 	
 	if( (api_is_course_admin() || api_is_course_coach() || api_is_course_tutor()) && !($my_thread) ){
 		// thread qualify
-
-		$form->addElement('static','Group','<a href="javascript://" onclick="if(document.getElementById(\'id_qualify\').style.display==\'none\'){ document.getElementById(\'id_qualify\').style.display=\'block\'; } else { document.getElementById(\'id_qualify\').style.display=\'none\'; }" ><br /><img src="../img/nolines_plus.gif" alt="" />'.get_lang('AdvancedParameters').'</a>');
+			
+		$form->addElement('static','Group','<a href="javascript://" onclick="return advanced_parameters()"><span id="img_plus_and_minus"><img src="../img/nolines_plus.gif" alt="" />'.get_lang('AdvancedParameters').'</span></a>');
 		$form->addElement('html','<div id="id_qualify" style="display:none">');
 		$form->addElement('static','Group', '<br /><strong>'.get_lang('AlterQualifyThread').'</strong>');
-		$form->addElement('checkbox', 'thread_qualify_gradebook', '', get_lang('QualifyThreadGradebook'));
-		$form->addElement('text', 'calification_notebook_title', get_lang('TitleColumnGradebook'));
-		$form->addElement('text', 'weight_calification', get_lang('QualifyWeight'),'Style="width:40px"');
 		$form->addElement('text', 'numeric_calification', get_lang('QualifyNumeric'),'Style="width:40px"');
+		$form->addElement('checkbox', 'thread_qualify_gradebook', '', get_lang('QualifyThreadGradebook'),'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">');
+		$form->addElement('text', 'calification_notebook_title', get_lang('TitleColumnGradebook'));
+		$form->addElement('text', 'weight_calification', get_lang('QualifyWeight'),'value="0.00" Style="width:40px" onfocus="this.select();"');
+		$form->addElement('html','</div>'); 
 	
 		$form->addElement('html','</div>');
 	}
@@ -1925,7 +1928,11 @@ function show_add_post_form($action='', $id='', $form_values='') {
 	if( $form->validate() ) {
 		$check = Security::check_token('post');	
 		if ($check) {
-	   		$values = $form->exportValues();
+	   		$values = $form->exportValues();	   		
+	   		if($values['thread_qualify_gradebook']=='1' && empty($values['weight_calification'])){
+				Display::display_error_message(get_lang('YouMustAssignWeightOfQualification').'&nbsp;<a href="javascript:window.back()">'.get_lang('Back').'</a>',false);
+	   			return false;	   		   						   				
+	   		}	   		
 	   		Security::clear_token();
 	   		return $values;
 		}
@@ -1958,7 +1965,7 @@ function show_add_post_form($action='', $id='', $form_values='') {
 function store_theme_qualify($user_id,$thread_id,$thread_qualify=0,$qualify_user_id=0,$qualify_time,$session_id=null) {
 	$table_threads_qualify = Database::get_course_table(TABLE_FORUM_THREAD_QUALIFY,'');
  	$table_threads		   =Database::get_course_table(TABLE_FORUM_THREAD,'');
-		if ($user_id==strval(intval($user_id)) && $thread_id==strval(intval($thread_id)) && $thread_qualify==strval(intval($thread_qualify))) {
+		if ($user_id==strval(intval($user_id)) && $thread_id==strval(intval($thread_id)) && $thread_qualify==strval(floatval($thread_qualify))) {
 			
 		//testing
 		
@@ -1974,7 +1981,7 @@ function store_theme_qualify($user_id,$thread_id,$thread_qualify=0,$qualify_user
 			if ($row[0]==0) {
 				$sql="INSERT INTO $table_threads_qualify (user_id," .
 					"thread_id,qualify,qualify_user_id,qualify_time,session_id)" .
-					"VALUES('".$user_id."','".$thread_id."','".$thread_qualify."'," .
+					"VALUES('".$user_id."','".$thread_id."',".(float)$thread_qualify."," .
 					"'".$qualify_user_id."','".$qualify_time."','".$session_id."')";
 				$res=api_sql_query($sql,__FILE__,__LINE__);
 			
@@ -2086,7 +2093,7 @@ function store_qualify_historical($option,$couser_id,$forum_id,$user_id,$thread_
 		//insert thread_historical
 		$sql1="INSERT INTO $table_threads_qualify_log (user_id," .
 				"thread_id,qualify,qualify_user_id,qualify_time,session_id)" .
-				"VALUES('".$user_id."','".$thread_id."','".$row[0]."'," .
+				"VALUES('".$user_id."','".$thread_id."',".(float)$row[0]."," .
 				"'".$qualify_user_id."','".$row[1]."','')";
 		api_sql_query($sql1,__FILE__,__LINE__);
 				
@@ -2258,14 +2265,22 @@ function show_edit_post_form($current_post, $current_thread, $current_forum, $fo
 	$form->addElement('html_editor', 'post_text', get_lang('Text'));
 	if (!isset($_GET['edit'])) {
 		
-		$form->addElement('static','Group','<a href="javascript://" onclick="if(document.getElementById(\'id_qualify\').style.display==\'none\'){ document.getElementById(\'id_qualify\').style.display=\'block\'; } else { document.getElementById(\'id_qualify\').style.display=\'none\'; }" ><br /><img src="../img/nolines_plus.gif" alt="" />'.get_lang('AdvancedParameters').'</a>');
+		$form->addElement('static','Group','<a href="javascript://" onclick="return advanced_parameters()"><span id="img_plus_and_minus"><img src="../img/nolines_plus.gif" alt="" />'.get_lang('AdvancedParameters').'</span></a>');
 		$form->addElement('html','<div id="id_qualify" style="display:none">');
 		$form->addElement('static','Group','<strong>'.get_lang('AlterQualifyThread').'</strong>');
-		$form->addElement('checkbox', 'thread_qualify_gradebook', '', get_lang('QualifyThreadGradebook'));
+		$form->addElement('text', 'numeric_calification', get_lang('QualifyNumeric'),'value="'.$current_thread['thread_qualify_max'].'" Style="width:40px"');
+		$form->addElement('checkbox', 'thread_qualify_gradebook', '', get_lang('QualifyThreadGradebook'),'onclick="javascript:if(this.checked==true){document.getElementById(\'options_field\').style.display = \'block\';}else{document.getElementById(\'options_field\').style.display = \'none\';}"');		
 		$defaults['thread_qualify_gradebook']=is_resource_in_course_gradebook(api_get_course_id(),5,$_GET['thread'],api_get_session_id());
+				
+		if (!empty($defaults['thread_qualify_gradebook'])) {
+		$form -> addElement('html','<div id="options_field" style="display:block">');
+		} else {
+			$form -> addElement('html','<div id="options_field" style="display:none">');
+		}						
 		$form->addElement('text', 'calification_notebook_title', get_lang('TitleColumnGradebook'),'value="'.$current_thread['thread_title_qualify'].'"');
-		$form->addElement('text', 'weight_calification', get_lang('QualifyWeight'),'value="'.$current_thread['thread_weight'].'" Style="width:40px"');
-		$form->addElement('text', 'numeric_calification', get_lang('QualifyNumeric'),'value="'.$current_thread['thread_qualify_max'].'" Style="width:40px"');
+		$form->addElement('text', 'weight_calification', get_lang('QualifyWeight'),'value="'.$current_thread['thread_weight'].'" Style="width:40px"');		
+		$form->addElement('html','</div>');
+		
 		$form->addElement('html','</div>');
 		//add gradebook
 	}
@@ -2312,6 +2327,10 @@ function show_edit_post_form($current_post, $current_thread, $current_forum, $fo
 	// The validation or display
 	if( $form->validate() ) {
 	   $values = $form->exportValues();
+	   if($values['thread_qualify_gradebook']=='1' && empty($values['weight_calification'])){
+				Display::display_error_message(get_lang('YouMustAssignWeightOfQualification').'&nbsp;<a href="javascript:window.back()">'.get_lang('Back').'</a>',false);
+	   			return false;	   		   						   				
+	   }	
 	   return $values;
 	} else {
 		$form->display();
diff --git a/main/forum/newthread.php b/main/forum/newthread.php
index 427abb3b02..b86bd1b5c5 100644
--- a/main/forum/newthread.php
+++ b/main/forum/newthread.php
@@ -90,6 +90,19 @@ if(isset($_GET['origin'])) {
 	$origin =  Security::remove_XSS($_GET['origin']);
 }
 
+// javascript
+$htmlHeadXtra[] = '<script>
+		
+		function advanced_parameters() {
+			if(document.getElementById(\'id_qualify\').style.display == \'none\') {
+				document.getElementById(\'id_qualify\').style.display = \'block\';
+				document.getElementById(\'img_plus_and_minus\').innerHTML=\'&nbsp;<img src="../img/nolines_minus.gif" alt="" />&nbsp;'.get_lang('AdvancedParameters').'\';
+			} else {
+				document.getElementById(\'id_qualify\').style.display = \'none\';
+				document.getElementById(\'img_plus_and_minus\').innerHTML=\'&nbsp;<img src="../img/nolines_plus.gif" alt="" />&nbsp;'.get_lang('AdvancedParameters').'\';
+			}	
+		}
+</script>';	
 /*
 ==============================================================================
 		MAIN DISPLAY SECTION
diff --git a/main/forum/viewforum.php b/main/forum/viewforum.php
index 5b91a1a7cc..68475a00a4 100644
--- a/main/forum/viewforum.php
+++ b/main/forum/viewforum.php
@@ -236,24 +236,33 @@ if ($my_action == 'liststd' AND isset($_GET['content']) AND isset($_GET['id']) A
 		$table_list.= '</tr>';
 		$max_qualify=show_qualify('2',$_GET['cidReq'],$my_forum,$userid,$_GET['id']);
 		$counter_stdlist=0;	
-		while ($row_student_list=Database::fetch_array($student_list)) {
-			if ($counter_stdlist%2==0) {
-					 $class_stdlist="row_odd";
+			
+		if (Database::num_rows($student_list)>0) {
+			while ($row_student_list=Database::fetch_array($student_list)) {
+				if ($counter_stdlist%2==0) {
+						 $class_stdlist="row_odd";
+				} else {
+						$class_stdlist="row_even";
+				}
+				$name_user_theme = 	$row_student_list['firstname'].' '.$row_student_list['lastname'];					
+				$table_list.= '<tr class="$class_stdlist"><td><a href="../user/userInfo.php?uInfo='.$row_student_list['user_id'].'&tipo=sdtlist&'.api_get_cidreq().'&forum='.Security::remove_XSS($my_forum).$origin_string.'">'.$name_user_theme.'</a></td>';
+				if ($_GET['list']=='qualify') {
+					$table_list.= '<td>'.$row_student_list['qualify'].'/'.$max_qualify.'</td>';
+				}
+				if ($userinf['status']=='1') {
+					$current_qualify_thread=show_qualify('1',$_GET['cidReq'],$my_forum,$row_student_list['user_id'],$_GET['id']);					
+					$table_list.= '<td><a href="forumqualify.php?'.api_get_cidreq().'&forum='.Security::remove_XSS($my_forum).'&thread='.Security::remove_XSS($_GET['id']).'&user='.$row_student_list['user_id'].'&user_id='.$row_student_list['user_id'].'&idtextqualify='.$current_qualify_thread.'&origin='.$origin.'">'.icon('../img/'.$icon_qualify,get_lang('Qualify')).'</a></td></tr>';
+				}
+				$counter_stdlist++;
+			}	
+		} else {
+			if ($_GET['list']=='qualify'){
+				$table_list.='<tr><td colspan="2">'.get_lang('ThereIsNotQualifiedLearners').'</td></tr>';	
 			} else {
-					$class_stdlist="row_even";
-			}
-			$name_user_theme = 	$row_student_list['firstname'].' '.$row_student_list['lastname'];					
-			$table_list.= '<tr class="$class_stdlist"><td><a href="../user/userInfo.php?uInfo='.$row_student_list['user_id'].'&tipo=sdtlist&'.api_get_cidreq().'&forum='.Security::remove_XSS($my_forum).$origin_string.'">'.$name_user_theme.'</a></td>';
-			if ($_GET['list']=='qualify') {
-				$table_list.= '<td>'.$row_student_list['qualify'].'/'.$max_qualify.'</td>';
-			}
-			if ($userinf['status']=='1') {
-				$current_qualify_thread=show_qualify('1',$_GET['cidReq'],$my_forum,$row_student_list['user_id'],$_GET['id']);					
-				$table_list.= '<td><a href="forumqualify.php?'.api_get_cidreq().'&forum='.Security::remove_XSS($my_forum).'&thread='.Security::remove_XSS($_GET['id']).'&user='.$row_student_list['user_id'].'&user_id='.$row_student_list['user_id'].'&idtextqualify='.$current_qualify_thread.'&origin='.$origin.'">'.icon('../img/'.$icon_qualify,get_lang('Qualify')).'</a></td></tr>';
-			}
-			$counter_stdlist++;
-		}	
-							
+				$table_list.='<tr><td colspan="2">'.get_lang('ThereIsNotUnqualifiedLearners').'</td></tr>';
+			}				
+		}
+				
 		$table_list.= '</table></center>';
 		$table_list .= '<br /></div>';
 	} else {