We are trying to build and test mpl installers for python2.4, 2.5 and 2.6. What we are finding is that if we build mpl against a more recent numpy than the installed numpy on a test machine, the import of mpl extension modules which depend on numpy trigger a segfault. Eg, on python2.5 and python2.6, we build the mpl installers against the numpy-1.3.0-win32.superpack installation, and if I test the installer on a python2.5 machine with numpy-1.2.1-win32.superpack installed, I get the segfault. If I install numpy-1.3.0-win32.superpack on the test machine, then the mpl binaries work fine. Is there an known binary incompatibly between 1.2.1 and 1.3.0? One solution we may consider is building our 2.5 binaries against 1.2.1 and seeing if they work with both 1.2.1 and 1.3.0 installations, but wanted to check in here to see if there were known issues or solutions we should be considering. Our test installers are at http://drop.io/rlck8ph if you are interested. Thanks, JDH