diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 91c09f1226a..417cb3042b7 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -5739,10 +5739,12 @@ abstract class CommonObject
 					$this->array_options["options_".$key] = price2num($this->array_options["options_".$key]);
 					break;
 				case 'date':
-					$this->array_options["options_".$key] = $this->db->idate($this->array_options["options_".$key]);
-					break;
 				case 'datetime':
-					$this->array_options["options_".$key] = $this->db->idate($this->array_options["options_".$key]);
+					if (empty($this->array_options["options_".$key])) {
+						$this->array_options["options_".$key] = null;
+					} else {
+						$this->array_options["options_".$key] = $this->db->idate($this->array_options["options_".$key]);
+					}
 					break;
 				/*
 				case 'link':
@@ -5790,7 +5792,11 @@ abstract class CommonObject
 			}
 
 			if ($linealreadyfound) {
-				$sql = "UPDATE ".MAIN_DB_PREFIX.$this->table_element."_extrafields SET ".$key." = '".$this->db->escape($this->array_options["options_".$key])."'";
+				if ($this->array_options["options_".$key] === null) {
+					$sql = "UPDATE ".MAIN_DB_PREFIX.$this->table_element."_extrafields SET ".$key." = null";
+				} else {
+					$sql = "UPDATE ".MAIN_DB_PREFIX.$this->table_element."_extrafields SET ".$key." = '".$this->db->escape($this->array_options["options_".$key])."'";
+				}
 				$sql .= " WHERE fk_object = ".$this->id;
 			} else {
 				$result = $this->insertExtraFields('', $user);