diff --git a/src/wuttjamaican/conf.py b/src/wuttjamaican/conf.py
index 7922a1f..081ad5a 100644
--- a/src/wuttjamaican/conf.py
+++ b/src/wuttjamaican/conf.py
@@ -329,6 +329,8 @@ class WuttaConfig:
             if not isinstance(value, configuration.Configuration):
                 return value
 
+            log.warning("ambiguous config key '%s' returns: %s", key, value)
+
         # read from db last if so requested
         if usedb and not preferdb:
             value = self.get_from_db(key, session=session)
diff --git a/tests/test_conf.py b/tests/test_conf.py
index 213a0e1..c0d95ae 100644
--- a/tests/test_conf.py
+++ b/tests/test_conf.py
@@ -336,6 +336,17 @@ configure_logging = true
 
         session.close()
 
+    def test_get_ambiguous(self):
+        config = conf.WuttaConfig()
+
+        # value is returned if key is not ambiguous
+        config.setdefault('foo', 'bar')
+        self.assertEqual(config.get('foo'), 'bar')
+
+        # but None is returned if key is ambiguous
+        config.setdefault('foo.bar', 'baz')
+        self.assertIsNone(config.get('foo'))
+
     def test_require(self):
         config = conf.WuttaConfig()
         self.assertRaises(ConfigurationError, config.require, 'foo')