gah.  i was tracking this down because I saw some strange errors that made me suspect it might exist (in 2.7) when trying to use a zipped up standard library but had not had time to confirm it. :(

I really should have rolled back the CLs causing it before 3.3.4 given that investigation was ongoing.  :(

We need to fix this breakage before 3.4.0 release.  The best thing to do for 3.4.0 is likely be to revert the following change:
 http://hg.python.org/cpython/rev/20b77ff040b6

For 3.3 the change that caused this is likely:
  http://hg.python.org/cpython/rev/2807a5f011e4

reverting that would restore the previous behavior.

Paul, are you in a position to try building 3.3.4 with that CL reverted to confirm?

We need better zipimport tests.
That test_zipimport passes while this problem exists is bad.

If you can come up with a reproducable test case for this, please go ahead and check it in to test_zipimport to highlight the brokenness.