diff --git a/htdocs/admin/modules.php b/htdocs/admin/modules.php
index 170e4ad0bce..65ea4f5a700 100644
--- a/htdocs/admin/modules.php
+++ b/htdocs/admin/modules.php
@@ -150,8 +150,8 @@ foreach ($modulesdir as $dir)
 
     					// We discard modules according to features level (PS: if module is activated we always show it)
     					$const_name = 'MAIN_MODULE_'.strtoupper(preg_replace('/^mod/i','',get_class($objMod)));
-    					if ($objMod->version == 'development'  && $conf->global->MAIN_FEATURES_LEVEL < 2 && ! $conf->global->$const_name) $modulequalified=0;
-    					if ($objMod->version == 'experimental' && $conf->global->MAIN_FEATURES_LEVEL < 1 && ! $conf->global->$const_name) $modulequalified=0;
+    					if ($objMod->version == 'development'  && $conf->global->MAIN_FEATURES_LEVEL < 2 && empty($conf->global->$const_name)) $modulequalified=0;
+    					if ($objMod->version == 'experimental' && $conf->global->MAIN_FEATURES_LEVEL < 1 && empty($conf->global->$const_name)) $modulequalified=0;
 
     					if ($modulequalified)
     					{