diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 8c9d966cef7..d411321386b 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -6461,6 +6461,14 @@ abstract class CommonObject
 							dol_syslog('Error bad setup of extrafield', LOG_WARNING);
 						}
 						break;
+					case 'checkbox':
+					case 'chkbxlst':
+						if (is_array($this->array_options[$key])) {
+							$new_array_options[$key] = implode(',', $this->array_options[$key]);
+						} else {
+							$new_array_options[$key] = $this->array_options[$key];
+						}
+						break;
 				}
 			}
 
@@ -6814,6 +6822,14 @@ abstract class CommonObject
 					}
 					break;
 				*/
+				case 'checkbox':
+				case 'chkbxlst':
+					if (is_array($this->array_options[$key])) {
+						$new_array_options[$key] = implode(',', $this->array_options[$key]);
+					} else {
+						$new_array_options[$key] = $this->array_options[$key];
+					}
+					break;
 			}
 
 			$this->db->begin();