Merged revisions 79871 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r79871 | mark.dickinson | 2010-04-06 23:10:55 +0100 (Tue, 06 Apr 2010) | 2 lines

  Use consistent spelling for nans (thanks Georg for noticing).
........