Weird forces

[Kyle]

Dear experts,

Here's the information about our platform:

kernel :SMP 2.6.18-128 x86-64
compiler suite :Gnu 4.4.0-6 for C, C++, Fortran 77/90
BLAS/LAPACK : using Intel MKL 11.0.083 for x86-64
FFT library :FFTW 3.2.2
ScaLAPACK : 1.8, installed using the Python ScaLAPACK installer script
MPI libraries : we used two libraries: OpenMPI 1.4.1 and MPICH2
1.2.1.  Neither of them worked well, and they gave apparently
different forces.
The cluster network is Infiniband-based, but this may not matter
because the error occurs even when running MPI job with a single
processor.

Here are the makefiles that we used to compile:

When using MPICH2:
----------------------------------------------------------------------------------------------
CC       = gcc44
CPP      =

FC       = /share/apps/cp2k/mpich/bin/mpif90 -I/share/apps/cp2k/
fftw-3.2.2/include/
LD       = /share/apps/cp2k/mpich/bin/mpif90 -L/share/apps/cp2k/
fftw-3.2.2/lib/ -L/share/apps/cp2k/scalapack/lib

AR       = ar -r

CPPFLAGS =
DFLAGS   = -D__GFORTRAN -D__FFTSG -D__FFTW3 -D__parallel -D__BLACS -
D__SCALAPACK
FCFLAGS  = -O2 -ffast-math -funroll-loops -ftree-vectorize -
march=native -ffree-form $(DFLAGS)
LDFLAGS  = $(FCFLAGS)
LIBS     = -lscalapack -lblacs -lblacsC -lblacsF77 -lblacs -
lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lpthread -lfftw3
OBJECTS_ARCHITECTURE = machine_gfortran.o
----------------------------------------------------------------------------------------------


When using OpenMPI:
----------------------------------------------------------------------------------------------
CC       = gcc4.4
CPP      =

FC       = mpif90 -I/share/apps/cp2k/fftw-3.2.2/include/
LD       = mpif90 -L/share/apps/cp2k/fftw-3.2.2/lib/ -L/share/apps/
scalapack/lib

AR       = ar -r

CPPFLAGS =
DFLAGS   = -D__GFORTRAN -D__FFTSG -D__FFTW3 -D__parallel -D__BLACS -
D__SCALAPACK
FCFLAGS  = -O2 -ffast-math -funroll-loops -ftree-vectorize -
march=native -ffree-form $(DFLAGS)
LDFLAGS  = $(FCFLAGS)
LIBS     = -lscalapack -lblacs -lblacsC -lblacsF77 -lblacs -
lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lpthread -lfftw3
OBJECTS_ARCHITECTURE = machine_gfortran.o
----------------------------------------------------------------------------------------------

Please let me know if any other information is needed.  We'll really
appreciate your help.

Thanks,

Best regards,
Kyle