title: tkagg backend problems
body: <p>I need to use the Tkagg backent to use matplotlib in a Tkinter program, and I received the "ImportError: No module named backend_tkagg" error message.</p>
  
  <p>Looking around, I saw as one possible solution that I add to install the agg-dev libs, so I did (Fedora fc13 here): <em>yum install agg agg-devel</em>
  ... but the problem persisted.</p>
  
  <p>I thought that maybe I had to reinstall matplotlib, so I issued a *easy_install -m matplotlib*, but no luck (though the same error message seems to come from a different file now, namely /usr/lib64/python2.6/site-packages/matplotlib/backends/<strong>init</strong>.py )</p>
  
  <p>any ideas?</p>