For those interested changing the "chunks=1" to "chunks=0" in http_server.py did in fact fix the incompatibility with MSIE and ZServer. Zope's, I don't consider this a bug with ZServer but with MSIE as this also plauged me using Frontier cgi's many times, the fix was the same. So I'm not creating a bug report unless you want this documented. DAve.
I too have noticed this on occasion. I believe that the problem has to do with ZServer's attempt at chunking responses.
The next version of ZServer will significantly alter the way ZServer handles HTTP response munging issues like this, and hopefully will fix this problem.
Thanks for the bug report.
-Amos
P.S. Until then Brad Clements's advice to change use_chunked=1 to use_chunked=0 in medusa/http_server.py may help.
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