Hey, I just thought I would drop a short note to the list explaining in fewer words what Carlo said. The bottom line is that 5.8 and 5.6 are not binary compatible. This is an annoyance that affects many things, including the ifeffit interface. The solution is to go to the place where you unpacked ifeffit and cd to the wrappers/perl/ directory. Rebuild the ifeffit interface by doing make clean perl Makefile.PL make make install I don't think you'll actually need to reinstall athena, but it couldn't hurt. This is not a OSX-only, or debian-only problem. We will all have this annoyance when we get around to updating to perl 5.8 That doesn't make me happy, but I'll deal. Starting to distribute a big tarball with the ifeffit interface bundled with all my codes will actually go along way towards solving that problem. And, if you are not updating to perl 5.8 (or don't even grok what this discussion is about), then you will probably not be affected by this issue. Thanks Carlo! B Bruce Ravel e-mail: ravel@phys.washington.edu URL: http://feff.phys.washington.edu/~ravel/