unable to upgrade port py25-scipy

I have been having trouble for several weeks upgrading port py25-scipy. Today I did a port selfupdate and successfully upgraded g95 and tried to upgrade py25-scipy from from version 0.6.0_0. The attempted upgrade ends with: ------- building 'scipy.interpolate.dfitpack' extension error: extension 'scipy.interpolate.dfitpack' has Fortran sources but no Fortran compiler found Warning: the following items did not execute (for py25-scipy): org.macports.destroot org.macports.build Error: Unable to upgrade port: 1 ------- I tried this with the default variant and with the +g95 variant set explicitly. This is on a PowerPC G4 recently upgraded to Mac OS X 10.4.11. Any ideas?