Looking further down into your config.log, I see this: configure:5369: gfortran conftest.f90 /usr/bin/ld: Undefined symbols: ___dso_handle I think this indicates you need to update your Developer Tools to the latest version 2.4.1. You can get this for free from the Apple Developer site: http://developer.apple.com/tools/download/ --Russ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: OJP-212167 Department: Support netCDF Priority: Normal Status: Closed