diff -r 342ab95a1f4b -r f3b467aca485 mercurial/commands.py
--- a/mercurial/commands.py	Wed Sep 02 15:19:05 2015 -0400
+++ b/mercurial/commands.py	Wed Sep 02 23:50:45 2015 -0400
@@ -3971,6 +3971,7 @@
     section = None
     if name and '.' in name:
         name, section = name.split('.', 1)
+        section = section.lower()
 
     text = help.help_(ui, name, **opts)