diff --git a/core/ManifestBuilder.php b/core/ManifestBuilder.php
index 655f0bc1e..7d7e691ac 100644
--- a/core/ManifestBuilder.php
+++ b/core/ManifestBuilder.php
@@ -313,7 +313,7 @@ class ManifestBuilder {
 				self::parse_file($file);
 		}
 
-		$tables = DB::getConn()->tableList();
+		$tables = DB::isActive() ? DB::getConn()->tableList() : array();
 
 		$allClasses["parents"] = self::find_parents();
 		$allClasses["children"] = self::find_children();
@@ -508,4 +508,4 @@ class ManifestBuilder {
 }
 
 
-?>
\ No newline at end of file
+?>