I went through the compile process with openMPI - twice, using g95 and gfortran (the default install on my openSuSE11.0 setup).  It seems to have trouble finding the libraries, in particular libopen-pal.so.0
I've seen shared-library problems with some x86_64 packages that I contrib to SourceForge and I'm wondering if this is a known problem with openMPI?  I'm using a TYAN 32-processor SMP machine with openSuSE11.0 installed.  (I tried copying the shared object file(s) to /usr/lib and /usr/lib64)

This is STDERR output, the first time with g95 and then with gfortran:

linux-pouh:/usr/local/openmpi-1.2.8 # ./configure FC=/usr/local/g95-install64bi/bin/x86_64-suse-linux-gnu-g95 --
prefix=/usr/local/bin
configure: WARNING:  -fno-strict-aliasing has been added to CFLAGS
configure: WARNING:  -finline-functions has been added to CXXFLAGS
configure: WARNING: *** Did not find corresponding C type
configure: WARNING: *** Fortran 77 and Fortran 90 compilers are not link compatible
configure: WARNING: *** Disabling MPI Fortran 90/95 bindings
configure: WARNING: On Linux and --with-udapl was not specified
configure: WARNING: Not building the udapl BTL
configure: WARNING: Unknown architecture ... proceeding anyway
configure: WARNING: File locks may not work with NFS.  See the Installation and
users manual for instructions on testing and if necessary fixing this
linux-pouh:/usr/local/openmpi-1.2.8 # mpif90
mpif90: error while loading shared libraries: libopen-pal.so.0: cannot open shared object file: No such file or directory
linux-pouh:/usr/local/openmpi-1.2.8 #  

... now try gfortran ...

/usr/local/openmpi-1.2.8 # ./configure  --prefix=/usr/local/bin > configure_STDIO.txt
configure: WARNING:  -fno-strict-aliasing has been added to CFLAGS
configure: WARNING:  -finline-functions has been added to CXXFLAGS
configure: WARNING: *** Did not find corresponding C type
configure: WARNING: *** Corresponding Fortran 77 type (INTEGER*16) not supported
configure: WARNING: *** Skipping Fortran 90 type (INTEGER*16)
configure: WARNING: On Linux and --with-udapl was not specified
configure: WARNING: Not building the udapl BTL
configure: WARNING: Unknown architecture ... proceeding anyway
configure: WARNING: File locks may not work with NFS.  See the Installation and
users manual for instructions on testing and if necessary fixing this
linux-pouh:/usr/local/openmpi-1.2.8 # make all install > GFortMakeAllInstall_STDIO.txt
mpif90
libtool: install: warning: relinking `mca_maffinity_first_use.la'
libtool: install: warning: relinking `mca_maffinity_libnuma.la'
libtool: install: warning: relinking `mca_paffinity_linux.la'
libtool: install: warning: relinking `libopen-rte.la'

<snip!>

libtool: install: warning: relinking `mca_mpool_rdma.la'
libtool: install: warning: relinking `mca_mpool_sm.la'
libtool: install: warning: relinking `mca_pml_cm.la'
libtool: install: warning: relinking `mca_pml_ob1.la'
libtool: install: warning: relinking `mca_rcache_vma.la'
libtool: install: warning: relinking `mca_topo_unity.la'
linux-pouh:/usr/local/openmpi-1.2.8 # mpif90
mpif90: error while loading shared libraries: libopen-pal.so.0: cannot open shared object file: No such file or directory
linux-pouh:/usr/local/openmpi-1.2.8 #  
linux-pouh:/usr/local/openmpi-1.2.8 # cd /usr/local/lib
linux-pouh:/usr/local/lib # ls
libmca_common_sm.la        libmpi_cxx.so        libmpi_f77.so.0      libmpi.so.0.0.0       libopen-rte.la
libmca_common_sm.so        libmpi_cxx.so.0      libmpi_f77.so.0.0.0  libopen-pal.la        libopen-rte.so
libmca_common_sm.so.0      libmpi_cxx.so.0.0.0  libmpi.la            libopen-pal.so        libopen-rte.so.0
libmca_common_sm.so.0.0.0  libmpi_f77.la        libmpi.so            libopen-pal.so.0      libopen-rte.so.0.0.0
libmpi_cxx.la              libmpi_f77.so        libmpi.so.0          libopen-pal.so.0.0.0  openmpi