[mod_python] cgi handler bug?

[FreeBSD 4.7, python 2.2.2, Apache 2.0.43, mod_python 3.0.1]

When I try and run something using cgihandler, I get the following error:

[Fri Dec 20 16:54:25 2002] [error] [client 192.168.71.163] PythonHandler mod_python.cgihandler:   File "/usr/local/lib/python2.2/site-packages/mod_python/apache.py", line 764, in restore_nocgi
    for k in osenv:
[Fri Dec 20 16:54:25 2002] [error] [client 192.168.71.163] PythonHandler mod_python.cgihandler: RuntimeError: dictionary changed size during iteration

Looking at mod_python/apache.py:restore_nocgi(), this does:
    for k in osenv:
        del osenv[k]

This is never going to be legal in Python 2.2.  Shouldn't this be 

    for k in osenv.keys():
        del osenv[k]

?

Having made that change, and a few little fixes to the cgi program, (__name__
== "__main__" is no longer true, "foo-bar.py" is not a good name as "import
foo-bar" is a syntax error) my cgi now runs inside mod_python.  But the HTML
generated by the CGI is sent twice, so my page displays double.  I've added 
debugging and the HTML is only being sent from the script once, as far as I 
can tell.  (i.e. I print a string of length 2132 bytes, but View Page Info 
shows 4215 bytes.   No, I have no idea where the missing 49 bytes are!)

Any clues?

Greg.