diff --git a/plugin/nerdtree/bookmark.vim b/plugin/nerdtree/bookmark.vim
index 603da53..0d37b47 100644
--- a/plugin/nerdtree/bookmark.vim
+++ b/plugin/nerdtree/bookmark.vim
@@ -290,7 +290,7 @@ function! s:Bookmark.validate()
     else
         call s:Bookmark.CacheBookmarks(1)
         call nerdtree#renderView()
-        call s:echo(self.name . "now points to an invalid location. See :help NERDTreeInvalidBookmarks for info.")
+        call nerdtree#echo(self.name . "now points to an invalid location. See :help NERDTreeInvalidBookmarks for info.")
         return 0
     endif
 endfunction
diff --git a/plugin/nerdtree/path.vim b/plugin/nerdtree/path.vim
index 68d5021..58bb013 100644
--- a/plugin/nerdtree/path.vim
+++ b/plugin/nerdtree/path.vim
@@ -68,7 +68,7 @@ function! s:Path.changeToDir()
 
     try
         execute "cd " . dir
-        call s:echo("CWD is now: " . getcwd())
+        call nerdtree#echo("CWD is now: " . getcwd())
     catch
         throw "NERDTree.PathChangeError: cannot change CWD to " . dir
     endtry