mpiexec starts multiple processes of same rank 0

Hello everybody

I am using the new Intel Composer XE 2015 which comes with a version of Intel MPI. I have been using OPENMPI before and compiled with g++ and my programs ran fine. Now with the new Intel Compiler I am able to compile and run the application but if I execute for example mpiexec -n 12 test_program the programm is executed 12 times but all the time with rank 0 and the processes do not communicate and assume they are on their own. So i assume something is wrong with the mpiexec script or maybe some message passing daemon. Thanks in advance for your answers

Best

Alex