diff --git a/mozilla/mail/base/content/messenger.xul b/mozilla/mail/base/content/messenger.xul
index ecb0a3de435..896d75b2718 100644
--- a/mozilla/mail/base/content/messenger.xul
+++ b/mozilla/mail/base/content/messenger.xul
@@ -152,7 +152,7 @@
         <label id="folderpane-title" value="&folderPaneHeader.label;"/>
       </sidebarheader>
       
-      <tree id="folderTree" class="plain focusring" flex="1" seltype="single"
+      <tree id="folderTree" class="plain focusring" flex="1" seltype="single" selstyle="primary"
             context="folderPaneContext"
             disableKeyNavigation="true"
             datasources="rdf:null"