diff --git a/LCS/ACC/ACCbin/include/ACCbin/PR_MPI.h b/LCS/ACC/ACCbin/include/ACCbin/PR_MPI.h
index f9e8e336282caf8852f0cd5debd65c92c710511f..b0a3c76e618c2f31431696a51a45e6efcad791cc 100644
--- a/LCS/ACC/ACCbin/include/ACCbin/PR_MPI.h
+++ b/LCS/ACC/ACCbin/include/ACCbin/PR_MPI.h
@@ -52,7 +52,8 @@ public:
 			const string& 			aJobName, 
 			const vector<string>& 	nodes,
 			const string& 			aExecutable,
-			const string& 			aParamfile);
+			const string& 			aParamfile,
+			uint16					nrProcs);
 
 	PR_MPI(const PR_MPI&	other);
 
diff --git a/LCS/ACC/ACCbin/src/ApplController.cc b/LCS/ACC/ACCbin/src/ApplController.cc
index 5e55728925eeddbc96ab2050823f2fc1a3f23edb..fa3251bc6141b34c2304a15a50b0164c0e1d90d8 100644
--- a/LCS/ACC/ACCbin/src/ApplController.cc
+++ b/LCS/ACC/ACCbin/src/ApplController.cc
@@ -263,7 +263,7 @@ void ApplController::createParSubsets()
 		// by a python script, for final LOFAR we need to do this in SAS.
 		if (procPrefix == "InputAppl.Transpose") {
 			LOG_DEBUG("CS1_SPECIAL: calling prepare_CS1_InputSection.py");
-			nrProcs = system("/opt/lofar/bin/prepare_CS1_InputSection.py");
+			nrProcs = system("/opt/lofar/bin/prepare_CS1_InputSection.py")/256;
 			LOG_DEBUG_STR("nrOfProcesses calculated by script = " << nrProcs);
 		}
         
@@ -361,7 +361,8 @@ void ApplController::createParSubsets()
 									procName,
 									nodes,
 									basePS.getString(procPrefix + "._executable"),
-									fileName));
+									fileName,
+									nrProcs));
 			writeParSubset(basePS, procName, fileName);
 		}
 
diff --git a/LCS/ACC/ACCbin/src/PR_MPI.cc b/LCS/ACC/ACCbin/src/PR_MPI.cc
index 3207410ee551c19a72bfb838963b1a051c87cc54..02845a1bc0a30b033326c4df9fbdbbc1fdb5ab56 100644
--- a/LCS/ACC/ACCbin/src/PR_MPI.cc
+++ b/LCS/ACC/ACCbin/src/PR_MPI.cc
@@ -39,7 +39,8 @@ PR_MPI::PR_MPI(const string&			aHostName,
 			   const string&  			aJobName,
 			   const vector<string>& 	nodes,
 			   const string&  			aExecutable,
-			   const string&  			aParamFile)
+			   const string&  			aParamFile,
+			   uint16					nrProcs)
 	: ProcRule("MPIjob", aJobName, aExecutable, aParamFile)
 {
 	LOG_TRACE_OBJ_STR ("PR_MPI: constructor");
@@ -66,7 +67,7 @@ PR_MPI::PR_MPI(const string&			aHostName,
 									machinefileName.c_str(),
 									aExecutable.c_str(),
 									aParamFile.c_str(),
-									nodes.size());
+									nrProcs);
 		itsStopCmd  = formatString("ssh %s \"( cd /opt/lofar/bin ; ./stopMPI.sh %s ) \"", 
 									aHostName.c_str(),
 									aExecutable.c_str());
@@ -77,7 +78,7 @@ PR_MPI::PR_MPI(const string&			aHostName,
 									machinefileName.c_str(),
 									aExecutable.c_str(),
 									aParamFile.c_str(),
-									nodes.size());
+									nrProcs);
 		itsStopCmd  = formatString("./stopMPI.sh %s", 
 									aExecutable.c_str());
 	}