diff -r bc32bb0e909f -r 03f3ce7ca2a8 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Fri Apr 15 16:15:30 2011 +0200
+++ b/mercurial/cmdutil.py	Fri Apr 15 16:15:32 2011 +0200
@@ -435,6 +435,8 @@
         src = repo.wjoin(abssrc)
         state = repo.dirstate[abstarget]
 
+        util.checkfilename(abstarget)
+
         # check for collisions
         prevsrc = targets.get(abstarget)
         if prevsrc is not None: