Emacs, py-shell, and PyX results in a dead Python process

[Greg Novak]

I realize that this is a pretty esoteric question, but I'm not even
getting any traction on it by myself.  

PyX is a Python package for drawing graphs
(http://pyx.sourceforge.net).  It runs TeX behind the scenes to
produce output.

When I run python as an inferior process under Emacs and try to use
PyX, I get a mysterious error:

import pyx
g=pyx.graph.graphxy(width=8)
g.plot(pyx.graph.data.list([[1,2],[2,4],[3,9]],x=1,y=2))
g.writeEPSfile('gsn');

results in:

Process Python hangup

and the Python process is dead.  My suspicion is that this has
something to do with the fact that PyX is running TeX behind the
scenes, but I can't confirm that.  Another useful piece of information
is that if I run a plain old inferior shell under Emacs and then run
Python, it works.  Perusing the python-mode.el, shell-mode.el, and
comint.el source files didn't produce an obvious reason for the
different behavior.  Nor can I find the snippet of code that's
actually producing this error message.

I'm running emacs 21.3, the stock python-shell.el mode, and PyX 0.7.
I run Python with 'M-x py-shell'

Many thanks,
Greg