diff --git a/src/java/com/threerings/whirled/spot/client/SpotSceneDirector.java b/src/java/com/threerings/whirled/spot/client/SpotSceneDirector.java
index 8eccfb397..2aeb7deaf 100644
--- a/src/java/com/threerings/whirled/spot/client/SpotSceneDirector.java
+++ b/src/java/com/threerings/whirled/spot/client/SpotSceneDirector.java
@@ -1,5 +1,5 @@
 //
-// $Id: SpotSceneDirector.java,v 1.30 2003/06/03 21:41:33 ray Exp $
+// $Id: SpotSceneDirector.java,v 1.31 2003/08/13 00:11:03 mdb Exp $
 
 package com.threerings.whirled.spot.client;
 
@@ -176,10 +176,12 @@ public class SpotSceneDirector extends BasicDirector
             return;
         }
 
-        Log.info("Sending changeLocation request " + loc + ".");
+        int sceneId = _scdir.getScene().getId();
+        Log.info("Sending changeLocation request [scid=" + sceneId +
+                 ", loc=" + loc + "].");
 
         _pendingLoc = (Location)loc.clone();
-        _sservice.changeLocation(_ctx.getClient(), loc, new ConfirmListener() {
+        ConfirmListener clist = new ConfirmListener() {
             public void requestProcessed () {
                 _location = _pendingLoc;
                 _pendingLoc = null;
@@ -194,7 +196,8 @@ public class SpotSceneDirector extends BasicDirector
                     listener.requestFailed(new Exception(reason));
                 }
             }
-        });
+        };
+        _sservice.changeLocation(_ctx.getClient(), sceneId, loc, clist);
     }
 
     /**
diff --git a/src/java/com/threerings/whirled/spot/client/SpotService.java b/src/java/com/threerings/whirled/spot/client/SpotService.java
index d8cf5c36a..8e1e51cbf 100644
--- a/src/java/com/threerings/whirled/spot/client/SpotService.java
+++ b/src/java/com/threerings/whirled/spot/client/SpotService.java
@@ -1,5 +1,5 @@
 //
-// $Id: SpotService.java,v 1.15 2003/03/27 00:10:08 mdb Exp $
+// $Id: SpotService.java,v 1.16 2003/08/13 00:11:03 mdb Exp $
 
 package com.threerings.whirled.spot.client;
 
@@ -33,9 +33,10 @@ public interface SpotService extends InvocationService
      * location. The user will be removed from any cluster from which they
      * are an occupant.
      *
+     * @param sceneId the id of the scene in which to change location.
      * @param loc the location to which to move.
      */
-    public void changeLocation (Client client, Location loc,
+    public void changeLocation (Client client, int sceneId, Location loc,
                                 ConfirmListener listener);
 
     /**
diff --git a/src/java/com/threerings/whirled/spot/data/SpotMarshaller.java b/src/java/com/threerings/whirled/spot/data/SpotMarshaller.java
index ed552824e..0110d7b8b 100644
--- a/src/java/com/threerings/whirled/spot/data/SpotMarshaller.java
+++ b/src/java/com/threerings/whirled/spot/data/SpotMarshaller.java
@@ -1,5 +1,5 @@
 //
-// $Id: SpotMarshaller.java,v 1.4 2003/03/26 02:06:06 mdb Exp $
+// $Id: SpotMarshaller.java,v 1.5 2003/08/13 00:11:03 mdb Exp $
 
 package com.threerings.whirled.spot.data;
 
@@ -39,12 +39,12 @@ public class SpotMarshaller extends InvocationMarshaller
     public static final int CHANGE_LOCATION = 2;
 
     // documentation inherited from interface
-    public void changeLocation (Client arg1, Location arg2, ConfirmListener arg3)
+    public void changeLocation (Client arg1, int arg2, Location arg3, ConfirmListener arg4)
     {
-        ConfirmMarshaller listener3 = new ConfirmMarshaller();
-        listener3.listener = arg3;
+        ConfirmMarshaller listener4 = new ConfirmMarshaller();
+        listener4.listener = arg4;
         sendRequest(arg1, CHANGE_LOCATION, new Object[] {
-            arg2, listener3
+            new Integer(arg2), arg3, listener4
         });
     }
 
diff --git a/src/java/com/threerings/whirled/spot/server/SpotDispatcher.java b/src/java/com/threerings/whirled/spot/server/SpotDispatcher.java
index a95ddfa38..7254dba4e 100644
--- a/src/java/com/threerings/whirled/spot/server/SpotDispatcher.java
+++ b/src/java/com/threerings/whirled/spot/server/SpotDispatcher.java
@@ -1,5 +1,5 @@
 //
-// $Id: SpotDispatcher.java,v 1.4 2003/03/26 02:06:06 mdb Exp $
+// $Id: SpotDispatcher.java,v 1.5 2003/08/13 00:11:03 mdb Exp $
 
 package com.threerings.whirled.spot.server;
 
@@ -51,7 +51,7 @@ public class SpotDispatcher extends InvocationDispatcher
         case SpotMarshaller.CHANGE_LOCATION:
             ((SpotProvider)provider).changeLocation(
                 source,
-                (Location)args[0], (ConfirmListener)args[1]
+                ((Integer)args[0]).intValue(), (Location)args[1], (ConfirmListener)args[2]
             );
             return;
 
diff --git a/src/java/com/threerings/whirled/spot/server/SpotProvider.java b/src/java/com/threerings/whirled/spot/server/SpotProvider.java
index 614236495..93808a6a7 100644
--- a/src/java/com/threerings/whirled/spot/server/SpotProvider.java
+++ b/src/java/com/threerings/whirled/spot/server/SpotProvider.java
@@ -1,5 +1,5 @@
 //
-// $Id: SpotProvider.java,v 1.19 2003/07/18 01:58:38 eric Exp $
+// $Id: SpotProvider.java,v 1.20 2003/08/13 00:11:03 mdb Exp $
 
 package com.threerings.whirled.spot.server;
 
@@ -155,12 +155,18 @@ public class SpotProvider
     /**
      * Processes a {@link SpotService#changeLocation} request.
      */
-    public void changeLocation (ClientObject caller, Location loc,
+    public void changeLocation (ClientObject caller, int sceneId, Location loc,
                                 SpotService.ConfirmListener listener)
         throws InvocationException
     {
-        int sceneId = getCallerSceneId(caller);
         BodyObject source = (BodyObject)caller;
+        int cSceneId = getCallerSceneId(caller);
+        if (cSceneId != sceneId) {
+            Log.warning("Rejecting changeLocation for invalid scene " +
+                        "[user=" + source.who() + ", insid=" + cSceneId +
+                        ", wantsid=" + sceneId + ", loc=" + loc + "].");
+            throw new InvocationException(INVALID_LOCATION);
+        }
 
         // look up the scene manager for the specified scene
         SpotSceneManager smgr = (SpotSceneManager)