Fixing bug when teacher is no set

main/inc/footer.inc.php

@@ -89,6 +89,7 @@ if (get_setting('show_teacher_data')=='true') {
 	if (isset($id_course) && $id_course!=-1) {
 		echo '<span id="coursemanager">';
 		$mail=CourseManager::get_emails_of_tutors_to_course($id_course);
+		if (!empty($mail)) {		
 			if (count($mail)>1){
 				$bar='&nbsp;|&nbsp;';
 				echo '&nbsp;'.get_lang('Teachers').' : ';
@@ -101,6 +102,7 @@ if (get_setting('show_teacher_data')=='true') {
 					echo Display::encrypted_mailto_link($email,$name).$bar;		
 				}
 			}
+		}
 		echo '</span>';
 	}