diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 4dc3b55c057..46d280f8763 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -3457,7 +3457,8 @@ abstract class CommonObject
 
     /**
      *	Add/Update all extra fields values for the current object.
-     *  All data to describe values to insert are stored into $this->array_options=array('keyextrafield'=>'valueextrafieldtoadd')
+     *  Data to describe values to insert/update are stored into $this->array_options=array('options_codeforfield1'=>'valueforfield1', 'options_codeforfield2'=>'valueforfield2', ...)
+     *  This function delte record with all extrafields and insert them again from the array $this->array_options.
      *
      *  @return int -1=error, O=did nothing, 1=OK
      */