[Wien] MPI parallel execution take much time than nonparallel on the same case on the multiprosesor single machine

[jam]

dear all
recently I switch to MPI parallel execution.I compile the
scalapack.2.0.1 and GotoBLAS2 and recompiled wien2k sources.bellow you
will see the compiler option which I set for compiling the wien2k.

Current settings:
 O   Compiler options:        -ffree-form -O2 -ffree-line-length-none
 L   Linker Flags:            $(FOPT) -L/home/GotoBLAS2 -lpthread
 P   Preprocessor flags       '-DParallel'
 R   R_LIB (LAPACK+BLAS):     -lgoto2 -lpthread


Current parallel compilation option settings:
     RP  RP_LIB(SCALAPACK+PBLAS): -lgoto2 -L/home/scalapack -lscalapack -lmpi -ldfftw_mpi -ldfftw
     FP  FPOPT(par.comp.options): -ffree-form -O2
     MP  MPIRUN commando        : mpirun -np _NP_ -machinefile _HOSTS_ _EXEC_

unfortunately upon execution on the same test case file the cycles execution fall in long time execution on lapw1para.
the .machines file is as bellow too:
1:localhost:3
granularity:1
extrafine:1

also I have set OMP_NUM_THREADS to 4 in .bashrc and the OS istalled on the machine is openSUSE-11.4.

I would appreciate if anyone can help me on the issue.
kind regard
hassan