diff --git a/mozilla/toolkit/xre/nsAppRunner.h b/mozilla/toolkit/xre/nsAppRunner.h
index d514230b30a..86eeb0e69f4 100644
--- a/mozilla/toolkit/xre/nsAppRunner.h
+++ b/mozilla/toolkit/xre/nsAppRunner.h
@@ -60,6 +60,11 @@
 // this key will not be available.
 #define NS_APP_PROFILE_DIR_STARTUP "ProfDS"
 
+// This directory service key is a lot like NS_APP_LOCALSTORE_50_FILE,
+// but it is always the "main" localstore file, even when we're in safe mode
+// and we load localstore from somewhere else.
+#define NS_LOCALSTORE_UNSAFE_FILE "LStoreS"
+
 class nsACString;
 struct nsXREAppData;
 struct nsStaticModuleInfo;
diff --git a/mozilla/toolkit/xre/nsXREDirProvider.cpp b/mozilla/toolkit/xre/nsXREDirProvider.cpp
index 999313ebbed..4005d45885d 100644
--- a/mozilla/toolkit/xre/nsXREDirProvider.cpp
+++ b/mozilla/toolkit/xre/nsXREDirProvider.cpp
@@ -262,10 +262,20 @@ nsXREDirProvider::GetFile(const char* aProperty, PRBool* aPersistent,
         rv = mProfileDir->Clone(getter_AddRefs(file));
         rv |= file->AppendNative(NS_LITERAL_CSTRING("prefs.js"));
       }
-      else if (!strcmp(aProperty, NS_APP_LOCALSTORE_50_FILE)) {
+      else if (!strcmp(aProperty, NS_LOCALSTORE_UNSAFE_FILE)) {
         rv = mProfileDir->Clone(getter_AddRefs(file));
         rv |= file->AppendNative(NS_LITERAL_CSTRING("localstore.rdf"));
-        EnsureProfileFileExists(file);
+      }
+      else if (!strcmp(aProperty, NS_APP_LOCALSTORE_50_FILE)) {
+        rv = mProfileDir->Clone(getter_AddRefs(file));
+        if (gSafeMode) {
+          rv |= file->AppendNative(NS_LITERAL_CSTRING("localstore-safe.rdf"));
+          file->Remove(PR_FALSE);
+        }
+        else {
+          rv |= file->AppendNative(NS_LITERAL_CSTRING("localstore.rdf"));
+          EnsureProfileFileExists(file);
+        }
       }
       else if (!strcmp(aProperty, NS_APP_HISTORY_50_FILE)) {
         rv = mProfileDir->Clone(getter_AddRefs(file));