diff --git a/ChangeLog b/ChangeLog
index 5db0806cb..cd59797a8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2009-11-06  Wolfgang Sourdeau  <wsourdeau@inverse.ca>
+
+	* UI/WebServerResources/UIxPreferences.js (_setupEvents): we check
+	whether "categoriesValue" resolves properly before assigning it
+	a new value.
+
 2009-11-05  Francis Lachapelle  <flachapelle@inverse.ca>
 
 	* UI/WebServerResources/ContactsUI.js (getMenus): activated the
diff --git a/UI/WebServerResources/UIxPreferences.js b/UI/WebServerResources/UIxPreferences.js
index 47933ad01..6b4f44718 100644
--- a/UI/WebServerResources/UIxPreferences.js
+++ b/UI/WebServerResources/UIxPreferences.js
@@ -60,7 +60,10 @@ function _setupEvents(enable) {
 
     $("replyPlacementList").observe ("change", onReplyPlacementListChange);
     $("composeMessagesType").observe ("change", onComposeMessagesTypeChange);
-    $("categoriesValue").value = "";
+
+    var categoriesValue = $("categoriesValue");
+    if (categoriesValue)
+        categoriesValue.value = "";
 }
 
 function onChoiceChanged(event) {