diff --git a/setup.py b/setup.py
--- a/setup.py
+++ b/setup.py
@@ -40,7 +40,7 @@ requirements = [
     "waitress >= 0.8.8, < 1.2",
     "WebOb >= 1.7, < 1.8", # turbogears2 2.3.12 requires WebOb<1.8.0
     "backlash >= 0.1.2, < 1",
-    "TurboGears2 >= 2.3.10, < 3",
+    "TurboGears2 >= 2.3.10, < 2.4",
     "tgext.routes >= 0.2.0, < 1",
     "Beaker >= 1.7.0, < 2",
     "WebHelpers >= 1.3, < 1.4",