The easiest fix for me was to download the latest matplotlib sources and compile/install them manually:
$ tar -zxvf matplotlib-0.98.5.2.tar.gz
$ cd matplotlib-0.98.5.2
$ python setup.py build
$ python setup.py install
This is less than ideal, because now I'm not running a "stock" Fedora where all of my software updates are taken care of automagically, but the increase in work-load is negligible.
A work-around for the incompatibility between numpy and matplotlib that requires editing some of the python sources:
Or you can just upgrade to Fedora 10. Unfortunately that's not an option for me because of a closed proprietary device driver that relies on < 2.6.27 kernels. I haven't compiled my own kernels since FC1 days, and don't really feel like getting back into the habit.