diff --git a/org.eclipse.titan.designer/src/org/eclipse/titan/designer/core/ant/CliScriptGenerator.java b/org.eclipse.titan.designer/src/org/eclipse/titan/designer/core/ant/CliScriptGenerator.java
index c7c6a56bee03a9c33a2599fbe254697a7345a500..1e0ea575c1df100dc5c494d203ca842702a56e48 100644
--- a/org.eclipse.titan.designer/src/org/eclipse/titan/designer/core/ant/CliScriptGenerator.java
+++ b/org.eclipse.titan.designer/src/org/eclipse/titan/designer/core/ant/CliScriptGenerator.java
@@ -34,7 +34,8 @@ public final class CliScriptGenerator {
 	private static final String SHELL_SCRIPT_HEADER = "#!/usr/bin/env sh\n";
 	private static final String SHELL_SCRIPT_TEXT =
 			  "function help() {\n"
-			+ "\techo \"usage: " + SHELL_SCRIPT_NAME + " executable.jar config.cfg [-m|--mode execution_mode] [-p|--project project_name]\"\n"
+			+ "\techo \"usage: " + SHELL_SCRIPT_NAME + " executable.jar config.cfg [-m|--mode execution_mode] "
+			+ "[-p|--project project_name]  [-vmargs \"arguments_for_jvm\"]\"\n"
 			+ "\techo \"  -m|--mode [hc|host_controller|mc|main_controller|p|parallel|s|single]\"\n"
 			+ "}\n\n"
 			+ "function proc_mode() {\n"
@@ -64,11 +65,11 @@ public final class CliScriptGenerator {
 			+ "\tfi\n"
 			+ "\techo \"Starting the Host Controller...\"\n"
 			+ "\techo \"Connecting to ${localaddress}:${tcpport}...\"\n"
-			+ "\tjava -Dfile.encoding=UTF-8 -cp ${exe_file} org.eclipse.titan.${project}.generated.Parallel_main ${localaddress} ${tcpport}\n"
+			+ "\tjava ${vmargs} -cp ${exe_file} org.eclipse.titan.${project}.generated.Parallel_main ${localaddress} ${tcpport}\n"
 			+ "}\n\n"
 			+ "function start_mc() {\n"
 			+ "\techo \"Starting the Main Controller...\"\n"
-			+ "\tjava -Dfile.encoding=UTF-8 -cp ${exe_file} org.eclipse.titan.runtime.core.mctr.CliMain ${cfg_file}\n"
+			+ "\tjava ${vmargs} -cp ${exe_file} org.eclipse.titan.runtime.core.mctr.CliMain ${cfg_file}\n"
 			+ "}\n\n"
 			+ "function start_parallel() {\n"
 			+ "\techo \"Starting automatic execution in Parallel mode...\"\n"
@@ -80,7 +81,7 @@ public final class CliScriptGenerator {
 			+ "}\n\n"
 			+ "function start_single() {\n"
 			+ "\techo \"Starting execution in Single mode...\"\n"
-			+ "\tjava -Dfile.encoding=UTF-8 -cp ${exe_file} org.eclipse.titan.${project}.generated.Single_main ${cfg_file}\n"
+			+ "\tjava ${vmargs} -cp ${exe_file} org.eclipse.titan.${project}.generated.Single_main ${cfg_file}\n"
 			+ "}\n\n"
 			+ "if [ ! -e \"$(which java)\" ]; then\n"
 			+ "\techo \"java is not found.\"\n"
@@ -89,10 +90,11 @@ public final class CliScriptGenerator {
 			+ "exe_file=\"\"\n"
 			+ "project=\"\"\n"
 			+ "mode=\"parallel\"\n"
+			+ "vmargs=\"-Dfile.encoding=UTF-8\"\n"
 			+ "while [ -n \"$1\" ]; do\n"
 			+ "\tcase \"$1\" in\n"
-			+ "\t\t-h) help; exit 1;;\n"
-			+ "\t\t--help) help; exit 1;;\n"
+			+ "\t\t-h) help; exit 0;;\n"
+			+ "\t\t--help) help; exit 0;;\n"
 			+ "\t\t-m) \n"
 			+ "\t\t\tif [ -n \"$2\" ]; then\n"
 			+ "\t\t\t\tmode=$2; shift\n"
@@ -117,6 +119,12 @@ public final class CliScriptGenerator {
 			+ "\t\t\telse\n"
 			+ "\t\t\t\techo \"Project name option is empty. Using default: ${project}\"\n"
 			+ "\t\t\tfi;;\n"
+			+ "\t\t-vmargs)\n"
+			+ "\t\t\tif [ -n \"$2\" ]; then\n"
+			+ "\t\t\t\tvmargs=$2; shift\n"
+			+ "\t\t\telse\n"
+			+ "\t\t\t\techo \"VM arguments option is empty. Using default: \\\"${vmargs}\\\"\"\n"
+			+ "\t\t\tfi;;\n"
 			+ "\t\t*) \n"
 			+ "\t\t\tif [[ $1 =~ .*.(jar|zip) ]]; then\n"
 			+ "\t\t\t\texe_file=$1 \n"
@@ -306,6 +314,13 @@ public final class CliScriptGenerator {
 		if (shellScriptContent != null) {
 			File shellScriptFile = new File(jarFolderString + File.separator + SHELL_SCRIPT_NAME);
 			IOUtils.writeStringToFile(shellScriptFile, shellScriptContent);
+			try {
+				if (!shellScriptFile.setExecutable(true, false))
+					if (!shellScriptFile.setExecutable(true, true))
+						throw new SecurityException();
+			} catch (SecurityException e) {
+				ErrorReporter.logWarning("Setting execution permission for '" + SHELL_SCRIPT_NAME + "' failed.");
+			}
 			project.refreshLocal(IResource.DEPTH_INFINITE, null);
 		}
 		if (cmdScriptContent != null) {