Compiling Scilab 4.1.2 on Slackware 12.1 (linux) required 

 ./configure --without-pvm --with-gfortran

-- if I didn't use "--with-gfortran", I got compilation (linking) errors, 
   because S12.1 no longer has a libg2c; the errors were

   undefined reference to getarg_
   undefined reference to iargc_