Merged revisions 62420-62421,62423-62424 via svnmerge from

Merged revisions 62420-62421,62423-62424 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r62420 | mark.dickinson | 2008-04-20 20:30:05 +0200 (Sun, 20 Apr 2008) | 3 lines

  Even more fixes for alpha Tru64, this time for
  the phase and polar methods.
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  r62421 | mark.dickinson | 2008-04-20 22:38:48 +0200 (Sun, 20 Apr 2008) | 2 lines

  Add test for tanh(-0.) == -0. on IEEE 754 systems
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  r62423 | amaury.forgeotdarc | 2008-04-20 23:02:21 +0200 (Sun, 20 Apr 2008) | 3 lines

  Correct an apparent refleak in test_pkgutil: zipimport._zip_directory_cache contains
  info for all processed zip files, even when they are no longer used.
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  r62424 | mark.dickinson | 2008-04-20 23:39:04 +0200 (Sun, 20 Apr 2008) | 4 lines

  math.atan2 is misbehaving on Windows;  this patch
  should fix the problem in the same way that
  the cmath.phase problems were fixed.
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