test_shutdown() may fail on very slow buildbots like FreeBSD 6.4 just because
of the arbitrary timeout.

as the processor type on some Mac systems.  Also fix NameError in fallback
_mac_ver_gestalt function.  And remove out-of-date URL in docs.

the parent structure. Patch by Vlad Riscutia.

cleared by the garbage collector.  This fixes a segfault when an instance
and its type get caught in a reference cycle, and the instance's
deallocator calls one of the methods on the type (e.g. when subclassing
IOBase).

Diagnosis and patch by Davide Rizzo.

and add a note concerning its status.

Also, point to the various alternatives.

failure in name resolution.

Should fix a buildbot failure.

an overzealous DNS service (e.g. OpenDNS) redirects to a placeholder
Web site.

DNS service (e.g. OpenDNS) resolves a non-existent domain name.  The test
is now skipped instead.

The Python signal handler for SIGABRT is not called on os.abort() (only if the
signal is raised manually or sent by another process). Patch by Kamil Kisiel.

Python 3.1. callable() is again supported in Python 3.2.

OS X window manager connection in tk tests, use OS X Application Services
API calls instead.

subprocess.Popen.communicate() now also handles EINTR errors if the process has
only one pipe.

os.write() clamp the length to INT_MAX on Windows.

On FreeBSD, the SIGALRM signal is sometimes received by the reader thread.

test_tk or test_ttk_guionly under a username that is not currently logged
in to the console windowserver (as may be the case under buildbot or ssh).

shutdown, if globals()['__file__'] is None.

wasn't enabled at first.

the garbage collector while the Heap lock is held.

with known OS bugs

Share the list of platforms with known OS bugs with other tests. Patch written
by Charles-François Natali.