Fix problem with moving trees in XEmacs.

Moving trees up or down with XEmacs caused a problem when the tree is
at the beginning if the buffer or narrowed region.  This patch
protects the relevant calls to outline-flag-region so that they are
only executed if the range is valid.

lisp/ChangeLog

@@ -1,6 +1,8 @@
 2008-12-05  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org.el (org-target-link-regexp): Make buffer-local.
+	(org-move-subtree-down): Fix bug with trees at beginning of
+	buffer.
 
 2008-12-04  Carsten Dominik  <carsten.dominik@gmail.com>
 

lisp/org.el

@@ -5107,8 +5107,8 @@ is signaled in this case."
     (setq txt (buffer-substring beg end))
     (org-save-markers-in-region beg end)
     (delete-region beg end)
-    (outline-flag-region (1- beg) beg nil)
-    (outline-flag-region (1- (point)) (point) nil)
+    (or (= beg (point-min)) (outline-flag-region (1- beg) beg nil))
+    (or (bobp) (outline-flag-region (1- (point)) (point) nil))
     (let ((bbb (point)))
       (insert-before-markers txt)
       (org-reinstall-markers-in-region bbb)