diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 1b888efc8ca..b84d31ddae3 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -5810,7 +5810,12 @@ abstract class CommonObject
 					// Convert date into timestamp format (value in memory must be a timestamp)
 					if (in_array($extrafields->attribute_type[$key],array('date','datetime')))
 					{
-						$value = GETPOSTISSET($keyprefix.'options_'.$key.$keysuffix)?dol_mktime(GETPOST($keyprefix.'options_'.$key.$keysuffix."hour", 'int', 3), GETPOST($keyprefix.'options_'.$key.$keysuffix."min",'int',3), 0, GETPOST($keyprefix.'options_'.$key.$keysuffix."month",'int',3), GETPOST($keyprefix.'options_'.$key.$keysuffix."day",'int',3), GETPOST($keyprefix.'options_'.$key.$keysuffix."year",'int',3)):$this->db->jdate($this->array_options['options_'.$key]);
+						$datenotinstring = $this->array_options['options_' . $key];
+						if (! is_numeric($this->array_options['options_' . $key]))	// For backward compatibility
+						{
+							$datenotinstring = $this->db->jdate($datenotinstring);
+						}
+						$value = GETPOSTISSET($keyprefix.'options_'.$key.$keysuffix)?dol_mktime(GETPOST($keyprefix.'options_'.$key.$keysuffix."hour", 'int', 3), GETPOST($keyprefix.'options_'.$key.$keysuffix."min",'int',3), 0, GETPOST($keyprefix.'options_'.$key.$keysuffix."month",'int',3), GETPOST($keyprefix.'options_'.$key.$keysuffix."day",'int',3), GETPOST($keyprefix.'options_'.$key.$keysuffix."year",'int',3)):$datenotinstring;
 					}
 					// Convert float submited string into real php numeric (value in memory must be a php numeric)
 					if (in_array($extrafields->attribute_type[$key],array('price','double')))