Index: src/core/org/apache/jmeter/testelement/AbstractTestElement.java
===================================================================
--- src/core/org/apache/jmeter/testelement/AbstractTestElement.java	(revision 1197646)
+++ src/core/org/apache/jmeter/testelement/AbstractTestElement.java	(working copy)
@@ -256,21 +256,29 @@
         return jmp instanceof NullProperty ? defaultValue : jmp.getStringValue();
     }
 
-    protected void addProperty(JMeterProperty property) {
+    protected void addProperty(JMeterProperty property, boolean clone) {
+    	JMeterProperty propertyToPut = property;
+    	if(clone) {
+    		propertyToPut = property.clone();
+    	}
         if (isRunningVersion()) {
-            setTemporary(property);
+        	setTemporary(propertyToPut);
         } else {
             clearTemporary(property);
         }
         JMeterProperty prop = getProperty(property.getName());
 
         if (prop instanceof NullProperty || (prop instanceof StringProperty && prop.getStringValue().equals(""))) {
-            propMap.put(property.getName(), property);
+        	propMap.put(property.getName(), propertyToPut);
         } else {
-            prop.mergeIn(property);
+            prop.mergeIn(propertyToPut);
         }
     }
 
+    protected void addProperty(JMeterProperty property) {
+        addProperty(property, false);
+    }
+
     protected void clearTemporary(JMeterProperty property) {
         if (temporaryProperties != null) {
             temporaryProperties.remove(property);
@@ -382,7 +390,7 @@
         PropertyIterator iter = element.propertyIterator();
         while (iter.hasNext()) {
             JMeterProperty prop = iter.next();
-            addProperty(prop);
+            addProperty(prop, true);
         }
     }