>>> import pickle
>>> pickle.dumps(1e100000, 2)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/lib/python2.3/pickle.py", line 1386, in dumps
    Pickler(file, protocol, bin).dump(obj)
  File "/usr/lib/python2.3/pickle.py", line 231, in dump
    self.save(obj)
  File "/usr/lib/python2.3/pickle.py", line 293, in save
    f(self, obj) # Call unbound method with explicit self
  File "/usr/lib/python2.3/pickle.py", line 489, in
save_float
    self.write(BINFLOAT + pack('>d', obj))
SystemError: frexp() result out of range


Prior to BINFLOAT, float infinity could successfully be
pickled.  The right thing to do here seems to be to
catch the exception and fall back to a FLOAT (string
representation) token.