mercurial/commandserver.py

--- a/mercurial/commandserver.py	Fri Nov 08 14:42:09 2013 +0900
+++ b/mercurial/commandserver.py	Mon Nov 11 22:59:26 2013 +0100
@@ -184,7 +184,10 @@
         # persist between requests
         copiedui = self.ui.copy()
         self.repo.baseui = copiedui
-        self.repo.ui = self.repo.dirstate._ui = self.repoui.copy()
+        # clone ui without using ui.copy because this is protected
+        repoui = self.repoui.__class__(self.repoui)
+        repoui.copy = copiedui.copy # redo copy protection
+        self.repo.ui = self.repo.dirstate._ui = repoui
         self.repo.invalidate()
         self.repo.invalidatedirstate()