diff --git a/src/java/com/threerings/crowd/data/PlaceObject.dobj b/src/java/com/threerings/crowd/data/PlaceObject.dobj
index 6ef3aaa09..b3caaf62e 100644
--- a/src/java/com/threerings/crowd/data/PlaceObject.dobj
+++ b/src/java/com/threerings/crowd/data/PlaceObject.dobj
@@ -1,5 +1,5 @@
 //
-// $Id: PlaceObject.dobj,v 1.10 2002/08/14 19:07:49 mdb Exp $
+// $Id: PlaceObject.dobj,v 1.11 2002/09/13 00:20:43 mdb Exp $
 
 package com.threerings.crowd.data;
 
@@ -20,7 +20,13 @@ public class PlaceObject extends DObject
     /**
      * Contains an info record (of type {@link OccupantInfo}) for each
      * occupant that contains information about that occupant that needs
-     * to be known by everyone in the place.
+     * to be known by everyone in the place. <em>Note:</em> Don't obtain
+     * occupant info records directly from this set when on the server,
+     * use <code>PlaceManager.getOccupantInfo()</code> instead (along with
+     * <code>PlaceManager.updateOccupantInfo()</code>) because it does
+     * some special processing to ensure that readers and updaters don't
+     * step on one another even if they make rapid fire changes to a
+     * user's occupant info.
      */
     public DSet occupantInfo = new DSet();
 
diff --git a/src/java/com/threerings/crowd/data/PlaceObject.java b/src/java/com/threerings/crowd/data/PlaceObject.java
index 181a07d70..9b790338f 100644
--- a/src/java/com/threerings/crowd/data/PlaceObject.java
+++ b/src/java/com/threerings/crowd/data/PlaceObject.java
@@ -1,5 +1,5 @@
 //
-// $Id: PlaceObject.java,v 1.7 2002/08/14 19:07:49 mdb Exp $
+// $Id: PlaceObject.java,v 1.8 2002/09/13 00:20:43 mdb Exp $
 
 package com.threerings.crowd.data;
 
@@ -29,7 +29,13 @@ public class PlaceObject extends DObject
     /**
      * Contains an info record (of type {@link OccupantInfo}) for each
      * occupant that contains information about that occupant that needs
-     * to be known by everyone in the place.
+     * to be known by everyone in the place. <em>Note:</em> Don't obtain
+     * occupant info records directly from this set when on the server,
+     * use <code>PlaceManager.getOccupantInfo()</code> instead (along with
+     * <code>PlaceManager.updateOccupantInfo()</code>) because it does
+     * some special processing to ensure that readers and updaters don't
+     * step on one another even if they make rapid fire changes to a
+     * user's occupant info.
      */
     public DSet occupantInfo = new DSet();
 
diff --git a/src/java/com/threerings/crowd/server/LocationProvider.java b/src/java/com/threerings/crowd/server/LocationProvider.java
index be6005240..fcca2317b 100644
--- a/src/java/com/threerings/crowd/server/LocationProvider.java
+++ b/src/java/com/threerings/crowd/server/LocationProvider.java
@@ -1,5 +1,5 @@
 //
-// $Id: LocationProvider.java,v 1.16 2002/08/14 19:07:49 mdb Exp $
+// $Id: LocationProvider.java,v 1.17 2002/09/13 00:20:43 mdb Exp $
 
 package com.threerings.crowd.server;
 
@@ -107,12 +107,9 @@ public class LocationProvider
                 // remove them from any previous location
                 leaveOccupiedPlace(source);
 
-                // generate a new occupant info record and add it to the
-                // target location
-                OccupantInfo info = pmgr.buildOccupantInfo(source);
-                if (info != null) {
-                    place.addToOccupantInfo(info);
-                }
+                // generate a new occupant info record (which will add it
+                // to the target location)
+                pmgr.buildOccupantInfo(source);
 
                 // set the body's new location
                 source.setLocation(place.getOid());
diff --git a/src/java/com/threerings/crowd/server/PlaceManager.java b/src/java/com/threerings/crowd/server/PlaceManager.java
index 75fb599f0..d27f25417 100644
--- a/src/java/com/threerings/crowd/server/PlaceManager.java
+++ b/src/java/com/threerings/crowd/server/PlaceManager.java
@@ -1,5 +1,5 @@
 //
-// $Id: PlaceManager.java,v 1.32 2002/08/14 19:07:49 mdb Exp $
+// $Id: PlaceManager.java,v 1.33 2002/09/13 00:20:43 mdb Exp $
 
 package com.threerings.crowd.server;
 
@@ -7,6 +7,8 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Properties;
 
+import com.samskivert.util.HashIntMap;
+
 import com.threerings.presents.data.ClientObject;
 import com.threerings.presents.server.InvocationManager;
 
@@ -86,6 +88,38 @@ public class PlaceManager
         return _plobj;
     }
 
+    /**
+     * Returns the occupant info record for the user with the specified
+     * body oid, if they are an occupant of this room. Returns null
+     * otherwise.
+     */
+    public OccupantInfo getOccupantInfo (int bodyOid)
+    {
+        return (OccupantInfo)_occInfo.get(bodyOid);
+    }
+
+    /**
+     * Updates the occupant info for this room occupant. <em>Note:</em>
+     * This must be used rather than setting the occupant info directly to
+     * avoid possible complications due to rapid fire changes to a user's
+     * occupant info. The occupant info record supplied to this method
+     * must be one returned from {@link #getOccupantInfo}. For example:
+     *
+     * <pre>
+     * OccupantInfo info = _plmgr.getOccupantInfo(bodyOid);
+     * // ... modifications made to 'info'
+     * _plmgr.updateOccupantInfo(info);
+     * </pre>
+     */
+    public void updateOccupantInfo (OccupantInfo occInfo)
+    {
+        // update the canonical copy
+        _occInfo.put(occInfo.getBodyOid(), occInfo);
+        // clone the canonical copy and send out an event updating the
+        // distributed set with that clone
+        _plobj.updateOccupantInfo((OccupantInfo)occInfo.clone());
+    }
+
     /**
      * A place manager derived class is likely to have a corresponding
      * derived class of {@link com.threerings.crowd.data.PlaceObject} that
@@ -216,19 +250,28 @@ public class PlaceManager
     }
 
     /**
-     * Builds an occupant info record for the specified body object. This
-     * is called by the location services when a body enters a place. It
-     * should not be overridden by derived classes, they should override
-     * {@link #populateOccupantInfo}, which is set up for that sort of
-     * thing.
+     * Builds an occupant info record for the specified body object and
+     * inserts it into our place object. This is called by the location
+     * services when a body enters a place. It should not be overridden by
+     * derived classes, they should override {@link
+     * #populateOccupantInfo}, which is set up for that sort of thing.
      */
     public OccupantInfo buildOccupantInfo (BodyObject body)
     {
-        // create a new occupant info instance
         try {
+            // create a new occupant info instance
             OccupantInfo info = (OccupantInfo)
                 getOccupantInfoClass(body).newInstance();
+
+            // configure it with the appropriate values
             populateOccupantInfo(info, body);
+
+            // insert the occupant info into our canonical table
+            _occInfo.put(info.getBodyOid(), info);
+
+            // and insert it into the place object
+            _plobj.addToOccupantInfo(info);
+
             return info;
 
         } catch (Exception e) {
@@ -294,6 +337,9 @@ public class PlaceManager
             _plobj.removeFromOccupantInfo(key);
         }
 
+        // clear out their canonical (local) occupant info record
+        _occInfo.remove(bodyOid);
+
         // let our delegates know what's up
         applyToDelegates(new DelegateOp() {
             public void apply (PlaceManagerDelegate delegate) {
@@ -484,4 +530,7 @@ public class PlaceManager
 
     /** A list of the delegates in use by this manager. */
     protected ArrayList _delegates;
+
+    /** Used to keep a canonical copy of the occupant info records. */
+    protected HashIntMap _occInfo = new HashIntMap();
 }
diff --git a/src/java/com/threerings/whirled/spot/server/SpotSceneManager.java b/src/java/com/threerings/whirled/spot/server/SpotSceneManager.java
index 13637df6d..55b51b5a1 100644
--- a/src/java/com/threerings/whirled/spot/server/SpotSceneManager.java
+++ b/src/java/com/threerings/whirled/spot/server/SpotSceneManager.java
@@ -1,5 +1,5 @@
 //
-// $Id: SpotSceneManager.java,v 1.19 2002/09/12 23:04:04 ray Exp $
+// $Id: SpotSceneManager.java,v 1.20 2002/09/13 00:20:43 mdb Exp $
 
 package com.threerings.whirled.spot.server;
 
@@ -203,8 +203,7 @@ public class SpotSceneManager extends SceneManager
 
         // make sure they have an occupant info object in the place
         int bodyOid = source.getOid();
-        SpotOccupantInfo soi = (SpotOccupantInfo)
-            _plobj.occupantInfo.get(new Integer(bodyOid));
+        SpotOccupantInfo soi = (SpotOccupantInfo)getOccupantInfo(bodyOid);
         if (soi == null) {
             Log.warning("Aiya! Can't update non-existent occupant info " +
                         "with new location [where=" + where() +
@@ -231,7 +230,7 @@ public class SpotSceneManager extends SceneManager
 
         // update the location and broadcast to the place
         soi.locationId = locationId;
-        _plobj.updateOccupantInfo(soi);
+        updateOccupantInfo(soi);
 
         // figure out the cluster chat oid
         int clusterIdx = _sscene.getClusterIndex(locidx);