graphviz plugin problem

[izghitu@…]

Hello, I have 2 Fedora Core 4 servers with python-2.4.1-2

I installed the graphviz plugin for trac (I have trac 0.9.5) On the first server everything went smooth without any problems. However on the second server after doing everything just like on the first one I get this error when trying to use graphviz: Trac detected an internal error: [Errno 32] Broken pipe

Python traceback Traceback (most recent call last):

File "/usr/lib/python2.4/site-packages/trac/web/cgi_frontend.py", line 130, in run

dispatch_request(req.path_info, req, env)

File "/usr/lib/python2.4/site-packages/trac/web/main.py", line 139, in dispatch_request

dispatcher.dispatch(req)

File "/usr/lib/python2.4/site-packages/trac/web/main.py", line 107, in dispatch

resp = chosen_handler.process_request(req)

File "/usr/lib/python2.4/site-packages/trac/wiki/web_ui.py", line 92, in process_request

self._render_editor(req, db, page, preview=True)

File "/usr/lib/python2.4/site-packages/trac/wiki/web_ui.py", line 311, in _render_editor

infopage_html? = wiki_to_html(page.text, self.env, req, db)

File "/usr/lib/python2.4/site-packages/trac/wiki/formatter.py", line 747, in wiki_to_html

Formatter(env, req, absurls, db).format(wikitext, out, escape_newlines)

File "/usr/lib/python2.4/site-packages/trac/wiki/formatter.py", line 576, in format

self.handle_code_block(line)

File "/usr/lib/python2.4/site-packages/trac/wiki/formatter.py", line 546, in handle_code_block

self.out.write(self.code_processor.process(self.req, self.code_text))

File "/usr/lib/python2.4/site-packages/trac/wiki/formatter.py", line 108, in process

text = self.processor(req, text)

File "/usr/lib/python2.4/site-packages/trac/wiki/formatter.py", line 98, in _macro_processor

return macro_provider.render_macro(req, self.name, text)

File "/home/trac/scs/plugins/graphviz-0.6.3-py2.4.egg/graphviz/graphviz.py", line 169, in render_macro File "/home/trac/scs/plugins/graphviz-0.6.3-py2.4.egg/graphviz/graphviz.py", line 369, in launch

IOError: [Errno 32] Broken pipe

Please help Thank you