diff --git a/pelican/generators.py b/pelican/generators.py
index f2fa0e33..9fc98663 100644
--- a/pelican/generators.py
+++ b/pelican/generators.py
@@ -98,7 +98,7 @@ class Generator(object):
         if extensions is None:
             extensions = self.markup
         basename = os.path.basename(path)
-        if extensions is False or basename.endswith(extensions):
+        if extensions is False or basename.endswith(tuple(extensions)):
             return True
         return False