diff --git a/interface/lib/classes/tform_tpl_generator.inc.php b/interface/lib/classes/tform_tpl_generator.inc.php
index a2da27606e1f5ab1a78f177ffcbe648448c59336..49fd274a898e67ff6d955b052ce0d679a89e0ad8 100644
--- a/interface/lib/classes/tform_tpl_generator.inc.php
+++ b/interface/lib/classes/tform_tpl_generator.inc.php
@@ -268,7 +268,7 @@ class tform_tpl_generator {
 					case 'TEXT':
 						$type = 'text';
 						$typevalue = '';
-						$defaultValue = 'NULL';
+						$defaultValue = NULL;
 						break;
 					case 'DATE':
 						$type = 'date';