diff --git a/lib/Cake/TestSuite/Fixture/CakeFixtureManager.php b/lib/Cake/TestSuite/Fixture/CakeFixtureManager.php
index 4d726efbb..ea875af7e 100644
--- a/lib/Cake/TestSuite/Fixture/CakeFixtureManager.php
+++ b/lib/Cake/TestSuite/Fixture/CakeFixtureManager.php
@@ -175,7 +175,7 @@ class CakeFixtureManager {
 			return;
 		}
 
-		$sources = $db->listSources();
+		$sources = (array)$db->listSources();
 		$table = $db->config['prefix'] . $fixture->table;
 		$exists = in_array($table, $sources);