diff --git a/htdocs/core/class/commonobject.class.php b/htdocs/core/class/commonobject.class.php
index 8aca1998d75..e6a4874a57d 100644
--- a/htdocs/core/class/commonobject.class.php
+++ b/htdocs/core/class/commonobject.class.php
@@ -7556,6 +7556,10 @@ abstract class CommonObject
 	{
 		if (is_null($value)) return 'NULL';
 		elseif (preg_match('/^(int|double|real|price)/i', $fieldsentry['type'])) return $this->db->escape("$value");
+		elseif ($fieldsentry['type'] == 'boolean') {
+		    if ($value) return 'true';
+		    else return 'false';
+        }
 		else return "'".$this->db->escape($value)."'";
 	}