There are similar problems with integer shifts.  In the trunk:

>>> 1>>(2**40)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
OverflowError: long int too large to convert to int

and in Python 3.0:

>>> 1>>(2**40)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
OverflowError: Python int too large to convert to C long

These should probably by fixed, too, though at least the error
message is clear.

What should 1<<(2**31) do?