diff -r 3a1b0afdaf84 -r 66308e07402c plcopen/plcopen.py
--- a/plcopen/plcopen.py	Thu Aug 09 18:07:44 2007 +0200
+++ b/plcopen/plcopen.py	Fri Aug 10 16:14:33 2007 +0200
@@ -413,7 +413,12 @@
     def addPouVar(self, type, name):
         content = self.interface.getContent()
         if len(content) == 0 or content[-1]["name"] != "localVars":
-            self.interface.appendContent("localVars", PLCOpenClasses["varList"]())
+            content.append({"name" : "localVars", "value" : PLCOpenClasses["varList"]()})
+        else:
+            varlist = content[-1]["value"]
+            variables = varlist.getVariable()
+            if varlist.getConstant() or varlist.getRetain() or len(variables) > 0 and variables[0].getAddress():
+                content.append({"name" : "localVars", "value" : PLCOpenClasses["varList"]()})
         var = PLCOpenClasses["varListPlain_variable"]()
         var.setName(name)
         var_type = PLCOpenClasses["dataType"]()
@@ -438,7 +443,23 @@
                 content.remove(varlist)
                 break
     setattr(cls, "removePouVar", removePouVar)
-        
+    
+    def hasBlock(self, name):
+        if self.getBodyType() in ["FBD", "LD", "SFC"]:
+            for instance in self.getInstances():
+                if isinstance(instance, PLCOpenClasses["block"]) and instance.getInstanceName() == name:
+                    return True
+            for transition in self.transitions.getTransition():
+                result = transition.hasBlock(name)
+                if result:
+                    return result
+            for action in self.actions.getAction():
+                result = action.hasBlock(name)
+                if result:
+                    return result
+        return False
+    setattr(cls, "hasBlock", hasBlock)
+    
     def addTransition(self, name, type):
         if not self.transitions:
             self.addTransitions()
@@ -540,6 +561,14 @@
         self.body.updateElementName(old_name, new_name)
     setattr(cls, "updateElementName", updateElementName)
 
+    def hasBlock(self, name):
+        if self.getBodyType() in ["FBD", "LD", "SFC"]:
+            for instance in self.getInstances():
+                if isinstance(instance, PLCOpenClasses["block"]) and instance.getInstanceName() == name:
+                    return True
+        return False
+    setattr(cls, "hasBlock", hasBlock)
+
 cls = PLCOpenClasses.get("actions_action", None)
 if cls:
     setattr(cls, "setBodyType", setBodyType)
@@ -557,6 +586,14 @@
         self.body.updateElementName(old_name, new_name)
     setattr(cls, "updateElementName", updateElementName)
 
+    def hasBlock(self, name):
+        if self.getBodyType() in ["FBD", "LD", "SFC"]:
+            for instance in self.getInstances():
+                if isinstance(instance, PLCOpenClasses["block"]) and instance.getInstanceName() == name:
+                    return True
+        return False
+    setattr(cls, "hasBlock", hasBlock)
+
 cls = PLCOpenClasses.get("body", None)
 if cls:
     def appendContentInstance(self, name, instance):