diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 6775a8da98c..3d312fd1270 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2008-02-07  Timo Savola <timo.savola@iki.fi>
+
+	* startup.el (command-line-x-option-alist): Add --parent-id.
+
+	* term/x-win.el (x-handle-parent-id): New function.
+
 2008-02-07  Chris Moore  <christopher.ian.moore@gmail.com>
 
 	* mouse.el (x-fixed-font-alist): Use consistent capitalization for
diff --git a/lisp/term/x-win.el b/lisp/term/x-win.el
index f5ec4c27480..5ce1a03ddcc 100644
--- a/lisp/term/x-win.el
+++ b/lisp/term/x-win.el
@@ -190,6 +190,15 @@
   (setq initial-frame-alist (cons (cons 'name x-resource-name)
 				  initial-frame-alist)))
 
+;; Handle the --parent-id option.
+(defun x-handle-parent-id (switch)
+  (or (consp x-invocation-args)
+      (error "%s: missing argument to `%s' option" (invocation-name) switch))
+  (setq parent-id (string-to-number (car x-invocation-args))
+	x-invocation-args (cdr x-invocation-args))
+  (setq initial-frame-alist (cons (cons 'parent-id parent-id)
+				  initial-frame-alist)))
+
 (defvar x-display-name nil
   "The name of the X display on which Emacs was started.