diff --git a/after/ftplugin/c/textobj-function.vim b/after/ftplugin/c/textobj-function.vim
index 6fc7ee8..a2a0990 100644
--- a/after/ftplugin/c/textobj-function.vim
+++ b/after/ftplugin/c/textobj-function.vim
@@ -35,7 +35,7 @@ if exists('b:undo_ftplugin')
 else
   let b:undo_ftplugin = ''
 endif
-let b:undo_ftplugin .= 'unlet b:textobj_function_select'
+let b:undo_ftplugin .= 'unlet! b:textobj_function_select'
 
 " __END__
 " vim: foldmethod=marker
diff --git a/after/ftplugin/java/textobj-function.vim b/after/ftplugin/java/textobj-function.vim
index 43808b5..2e84f21 100644
--- a/after/ftplugin/java/textobj-function.vim
+++ b/after/ftplugin/java/textobj-function.vim
@@ -36,7 +36,7 @@ if exists('b:undo_ftplugin')
 else
   let b:undo_ftplugin = ''
 endif
-let b:undo_ftplugin .= 'unlet b:textobj_function_select'
+let b:undo_ftplugin .= 'unlet! b:textobj_function_select'
 
 " __END__
 " vim: foldmethod=marker
diff --git a/after/ftplugin/vim/textobj-function.vim b/after/ftplugin/vim/textobj-function.vim
index afcbd6b..d39f0c2 100644
--- a/after/ftplugin/vim/textobj-function.vim
+++ b/after/ftplugin/vim/textobj-function.vim
@@ -35,7 +35,7 @@ if exists('b:undo_ftplugin')
 else
   let b:undo_ftplugin = ''
 endif
-let b:undo_ftplugin .= 'unlet b:textobj_function_select'
+let b:undo_ftplugin .= 'unlet! b:textobj_function_select'
 
 " __END__
 " vim: foldmethod=marker