[103693] Fix JUnit tests
diff --git a/plugins/org.eclipse.jst.server.tomcat.core/tomcatcore/org/eclipse/jst/server/tomcat/core/internal/TomcatServerBehaviour.java b/plugins/org.eclipse.jst.server.tomcat.core/tomcatcore/org/eclipse/jst/server/tomcat/core/internal/TomcatServerBehaviour.java
index 3501af6..42ef3f6 100644
--- a/plugins/org.eclipse.jst.server.tomcat.core/tomcatcore/org/eclipse/jst/server/tomcat/core/internal/TomcatServerBehaviour.java
+++ b/plugins/org.eclipse.jst.server.tomcat.core/tomcatcore/org/eclipse/jst/server/tomcat/core/internal/TomcatServerBehaviour.java
@@ -522,7 +522,7 @@
 		workingCopy.setAttribute(IJavaLaunchConfigurationConstants.ATTR_PROGRAM_ARGUMENTS, mergeArguments(existingProgArgs, getRuntimeProgramArguments(true)));
 
 		String existingVMArgs = workingCopy.getAttribute(IJavaLaunchConfigurationConstants.ATTR_VM_ARGUMENTS, (String)null);
-		if (!getTomcatServer().isSecure()) {
+		if (existingVMArgs != null && !getTomcatServer().isSecure()) {
 			// remove -Djava.security.manager and -Djava.security.policy="x x"
 			int index = existingVMArgs.indexOf("-Djava.security.manager");
 			if (index >= 0) {