diff --git a/xpcom/tests/TestRegistrationOrder.cpp b/xpcom/tests/TestRegistrationOrder.cpp
index c0943a1862af..99fcfd0440a0 100644
--- a/xpcom/tests/TestRegistrationOrder.cpp
+++ b/xpcom/tests/TestRegistrationOrder.cpp
@@ -158,7 +158,7 @@ bool TestContractFirst()
 }
 
 static already_AddRefed<nsILocalFile>
-GetRegDirectory(const char* basename, const char* dirname)
+GetRegDirectory(const char* basename, const char* dirname, const char* leafname)
 {
     nsCOMPtr<nsILocalFile> f;
     nsresult rv = NS_NewNativeLocalFile(nsDependentCString(basename), PR_TRUE,
@@ -167,6 +167,7 @@ GetRegDirectory(const char* basename, const char* dirname)
         return NULL;
 
     f->AppendNative(nsDependentCString(dirname));
+    f->AppendNative(nsDependentCString(leafname));
     return f.forget();
 }
 
@@ -184,9 +185,9 @@ int main(int argc, char** argv)
   
   const char *regPath = argv[1];
   XRE_AddManifestLocation(NS_COMPONENT_LOCATION,
-                          nsCOMPtr<nsILocalFile>(GetRegDirectory(regPath, "core")));
+                          nsCOMPtr<nsILocalFile>(GetRegDirectory(regPath, "core", "component.manifest")));
   XRE_AddManifestLocation(NS_COMPONENT_LOCATION,
-                          nsCOMPtr<nsILocalFile>(GetRegDirectory(regPath, "extension")));
+                          nsCOMPtr<nsILocalFile>(GetRegDirectory(regPath, "extension", "extComponent.manifest")));
   ScopedXPCOM xpcom("RegistrationOrder");
   if (xpcom.failed())
     return 1;