I confirm that it works reliably under 3.2, while it hangs as reliably under 2.7 and 3.1. Since fixing involves a C extension that is too heavy to backport to bugfix branches, I suggest closing.

By the way: triagers, please don't set stage to "unit test needed". We don't need an unit test before a proper decision about the issue has been done, and actually we don't require reporters to write an unit test either (it's done as part of the patch, usually).