Bug: org-capture - org-vm store link requires buffer file not always present [7.4]

[Arik Mitschang <arik.mitschang@mq.edu.au>]

In VM if you have created a virtual folder, the buffer is not associated
with any file. However, during org-capture a function called
org-vm-store-link requires that the buffer (the vm folder in this case)
be associated with a file causing a type-mismatch error. I can fix the
problem with the following patch:

----------------------------------
diff -U3 /usr/local/share/emacs/23.2/site-lisp/org-vm.el /var/folders/Qm/Qm3iuPk7E18cewjBO5PgL5AVPiY/-Tmp-/buffer-content-66395kXL
--- /usr/local/share/emacs/23.2/site-lisp/org-vm.el	2010-12-11 00:16:33.000000000 +1100
+++ /var/folders/Qm/Qm3iuPk7E18cewjBO5PgL5AVPiY/-Tmp-/buffer-content-66395kXL	2011-02-09 14:27:35.000000000 +1100
@@ -54,8 +54,12 @@
 ;; Implementation
 (defun org-vm-store-link ()
   "Store a link to a VM folder or message."
-  (when (or (eq major-mode 'vm-summary-mode)
+  (when (and (or (eq major-mode 'vm-summary-mode)
 	    (eq major-mode 'vm-presentation-mode))
+			 (save-excursion (vm-select-folder-buffer)
+							 (eq (type-of buffer-file-name)
+							 'string)))
     (and (eq major-mode 'vm-presentation-mode) (vm-summarize))
     (vm-follow-summary-cursor)
     (save-excursion
----------------------------------

Thanks
Arik

Emacs  : GNU Emacs 23.2.1 (x86_64-apple-darwin10.5.0, X toolkit)
 of 2011-01-14 on IT-4064.local
Package: Org-mode version 7.4