combining mod_python handlers publisher and psp problem

[exhuma.twn]

Simple problem:

When I define a funtion the way you would with the publisher handler
(without using psp), all works as expected. However when I define a
publisher-like function and instantiate a PSP object in it ( as
suggested on
http://www.onlamp.com/pub/a/python/2004/02/26/python_server_pages.html
) mod_python seems to fail to tell the browser which content-type the
document has. The output is what I expect it to be, but instead of
rendering the page I see the source code, so I suppose the browser sees
it as "text/python" or "text/plain".

I tried to do a

   print "Content-Type: text/html"
   print

as first statement, but then it only outputs that as normal text too.

Any ideas?