I've built openmpi version 1.3.3 on a MacPro with OS X 10.5.8 and the Intel 10.1.006 Fortran compiler and gcc 4.0.  As far as I can tell, the configure and make commands completed fine. There are some warnings, but it's not clear to me that they are critical - or the explanation for what's not working. After installing, I try to compile a simple F77 hello world code. The output is:

% mpif77 helloworld_mpi.f -o helloworld_mpi
ld: warning in /opt/openmpi/lib/libmpi_f77.a, file is not of required architecture
Undefined symbols:
  "_mpi_init_", referenced from:
      _MAIN__ in ifortIsUNoZ.o
  "_mpi_comm_size_", referenced from:
      _MAIN__ in ifortIsUNoZ.o
  "_mpi_finalize_", referenced from:
      _MAIN__ in ifortIsUNoZ.o
  "_mpi_comm_rank_", referenced from:
      _MAIN__ in ifortIsUNoZ.o
ld: symbol(s) not found

I don't know what the warning about the "required architecture" means and cannot find any relevant info in the archives or with google. I'd appreciate any help. More info is below, including the config.log file as an attachment. 

Here's my configure command:

./configure --prefix=/opt/openmpi --enable-static --disable-shared CC=gcc CFLAGS=-m64 CXX=g++ CXXFLAGS=-m64 F77=ifort FC=ifort FFLAGS=-assume nounderscore FCFLAGS=-assume nounderscore

The output of the ompi_info --all command is also attached. 

Thanks,

Andreas