diff --git a/htdocs/core/class/html.form.class.php b/htdocs/core/class/html.form.class.php
index 4ce4d393355..c589e01d561 100644
--- a/htdocs/core/class/html.form.class.php
+++ b/htdocs/core/class/html.form.class.php
@@ -3441,7 +3441,7 @@ class Form
             $formconfirm.= '<tr class="valid">';
             $formconfirm.= '<td class="valid">'.$question.'</td>';
             $formconfirm.= '<td class="valid">';
-            $formconfirm.= $this->selectyesno("confirm",$newselectedchoice);
+            $formconfirm.= self::selectyesno("confirm",$newselectedchoice);
             $formconfirm.= '</td>';
             $formconfirm.= '<td class="valid" align="center"><input class="button" type="submit" value="'.$langs->trans("Validate").'"></td>';
             $formconfirm.= '</tr>'."\n";
@@ -5381,7 +5381,7 @@ class Form
      *  @param	int      	$useempty		1=Add empty line
      *	@return	mixed						See option
      */
-    function selectyesno($htmlname,$value='',$option=0,$disabled=false,$useempty='')
+    public static function selectyesno($htmlname,$value='',$option=0,$disabled=false,$useempty='')
     {
         global $langs;