diff --git a/src/sugar/wm.py b/src/sugar/wm.py
index d813d94..f781844 100644
--- a/src/sugar/wm.py
+++ b/src/sugar/wm.py
@@ -20,11 +20,37 @@ UNSTABLE. Used only internally by Activity and jarabe.
 """
 
 import gtk
+import logging
 
+def _property_get_trapped(window, prop, prop_type):
+    gtk.gdk.error_trap_push()
+
+    prop_info = window.property_get('_SUGAR_ACTIVITY_ID', 'STRING')
+
+    # We just log a message
+    error = gtk.gdk.error_trap_pop()
+    if gtk.gdk.error_trap_pop():
+        logging.debug('Recieved X Error (%i) while getting ' + \
+                      'a property on a window' % error)
+
+    return prop_info
+
+def _property_change_trapped(window, prop, prop_type, format, mode, data):
+    gtk.gdk.error_trap_push()
+
+    window.property_change(prop, prop_type, format, mode, data)
+
+    error = gtk.gdk.error_trap_pop()
+    if error:
+        logging.debug('Recieved X Error (%i) while setting ' + \
+                      'a property on a window' % error)
+        raise RuntimeError('Recieved X Error (%i) while setting ' + \
+                           'a property on a window' % error)
+    
 
 def get_activity_id(wnck_window):
     window = gtk.gdk.window_foreign_new(wnck_window.get_xid())
-    prop_info = window.property_get('_SUGAR_ACTIVITY_ID', 'STRING')
+    prop_info = _property_get_trapped(window, '_SUGAR_ACTIVITY_ID', 'STRING')
     if prop_info is None:
         return None
     else:
@@ -33,7 +59,7 @@ def get_activity_id(wnck_window):
 
 def get_bundle_id(wnck_window):
     window = gtk.gdk.window_foreign_new(wnck_window.get_xid())
-    prop_info = window.property_get('_SUGAR_BUNDLE_ID', 'STRING')
+    prop_info = _property_get_trapped(window, '_SUGAR_BUNDLE_ID', 'STRING')
     if prop_info is None:
         return None
     else:
@@ -41,10 +67,11 @@ def get_bundle_id(wnck_window):
 
 
 def set_activity_id(window, activity_id):
-    window.property_change('_SUGAR_ACTIVITY_ID', 'STRING', 8,
-                           gtk.gdk.PROP_MODE_REPLACE, activity_id)
+    _property_change_trapped(window, '_SUGAR_ACTIVITY_ID', 'STRING', 8,
+                             gtk.gdk.PROP_MODE_REPLACE, activity_id)
 
 
 def set_bundle_id(window, bundle_id):
-    window.property_change('_SUGAR_BUNDLE_ID', 'STRING', 8,
-                           gtk.gdk.PROP_MODE_REPLACE, bundle_id)
+    _property_change_trapped(window, '_SUGAR_BUNDLE_ID', 'STRING', 8,
+                             gtk.gdk.PROP_MODE_REPLACE, bundle_id)
+