A similar issue occurs on "x86 debian parallel" buildbot:
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FAIL: test_nonascii (test.test_warnings.CEnvironmentVariableTests)
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Traceback (most recent call last):
File "/home2/buildbot2/slave/3.x.loewis-parallel/build/Lib/test/test_warnings.py", line 731, in test_nonascii
"['ignore:DeprecaciónWarning']".encode('utf-8'))
AssertionError: b'' != b"['ignore:Deprecaci\xc3\xb3nWarning']"
http://www.python.org/dev/buildbot/builders/x86%20debian%20parallel%203.x/builds/80