diff --git a/Nasal/canvas/generic-canvas-map.xml b/Nasal/canvas/generic-canvas-map.xml
index 01a6151ac..30ab91e48 100644
--- a/Nasal/canvas/generic-canvas-map.xml
+++ b/Nasal/canvas/generic-canvas-map.xml
@@ -97,8 +97,8 @@ In the close block, you'll want to call "map.cleanup_listeners()" at the moment
 			.setupZoom( dialog:DIALOG_CANVAS ) 			# TODO: make zooming configurable for non GUI use
 			.pickupFeatures (DIALOG_CANVAS);			# set up the features specified in the XML file
 
-	 # FIXME: resource cleanup (listeners!)
-	update_info();
+	canvas.run_callbacks(); # WORKAROUND to run dialog-specific init code - 
+				# must be set up via register_callback() in the dialog's open block currently 
           ]]>
           </load>
         </nasal>
diff --git a/Nasal/canvas/map.nas b/Nasal/canvas/map.nas
index 768e6639a..aa144d27f 100644
--- a/Nasal/canvas/map.nas
+++ b/Nasal/canvas/map.nas
@@ -37,6 +37,12 @@
 #
 
 
+#FIXME: this is a hack so that dialogs can register their own
+# callbacks that are automatically invoked at the end of the
+# generic-canvas-map.xml file (canvas/nasal section)
+var callbacks = [];
+var register_callback = func(c) append(callbacks, c);
+var run_callbacks = func foreach(var c; callbacks) c();
 
 var DEBUG=0;
 if (DEBUG) {
@@ -418,7 +424,7 @@ LayeredMap.updateState = func {
 
  #FIXME: listener management should be done at the MVC level, for each component - not as part of the LayeredMap!
  LayeredMap.cleanup_listeners = func {
-  print("Cleaning up listeners");
+  # print("Cleaning up listeners");
   foreach(var l; me.listeners) 
 	removelistener(l);
         
diff --git a/gui/dialogs/airports.xml b/gui/dialogs/airports.xml
index ba9454030..47749fc6d 100644
--- a/gui/dialogs/airports.xml
+++ b/gui/dialogs/airports.xml
@@ -190,14 +190,13 @@
           }         
       }    
             
-      update_info();
-
+	canvas.register_callback(update_info); # FIXME: this is a workaround to run dialog-specific code in the canvas block
       ]]>
     </open>
     <close>
 	fgcommand("clear-metar", var n = props.Node.new({ "path": "/sim/gui/dialogs/airports/selected-airport/metar",
                                                              "station": airport_id}));
-        # map.cleanup_listeners(); #TODO: We should be setting a signal when closing the dialog, so that cleanup code can be invoked automatically
+        map.cleanup_listeners(); #TODO: We should be setting a signal when closing the dialog, so that cleanup code can be invoked automatically
     </close>
   </nasal>
   
@@ -657,6 +656,7 @@
 		<description>Show Tower</description>
 		<default>enabled</default>
         </layer>
+
 	<!-- Uncomment this to add a navaid layer (not yet fully implemented, and no LOD yet)
  	<layer>
                 <name>navaids</name>