As it says on the tin. I think $page might need to be lowercased in editpage.pm. Workaround until then is to change the setting to 'discussion'.
+
+> [[news/version_20111106]] says: "Fix handling of discussion page creation
+> links to make discussion pages in the right place and with the right case.
+> Broken by page case preservation feature added in 3.20110707." So I think
+> this is probably [[done]]? --[[smcv]]