[O] Error in post-command-hook: (void-variable org-ans1)

[Diep Pham Van]

I get this error: "Error in post-command-hook: (void-variable
org-ans1)" every time I want to use schedule or deadline. After that,
the error message appear with any command. After some minutes, this
error message disappear and I can use anny command as expected.

This problem happens with both the version ship with emacs 23.3 or
latest version (7.7).

This is my .emacs config.

http://pastebin.com/sQaTYJCR

C-h v post-command-hook before the problem appear:

post-command-hook is a variable defined in `C source code'.
Its value is
(linum-update-current ac-handle-post-command
autopair-post-command-handler t)

Local in buffer .emacs; global value is 
(global-font-lock-mode-check-buffers global-linum-mode-check-buffers
global-auto-complete-mode-check-buffers
autopair-global-mode-check-buffers yas/global-mode-check-buffers
global-hl-line-highlight)

After:
post-command-hook\ \ \  is void as a variable.

Documentation:
Not documented as a variable.

I've search around and still could not solve the problem.
Anyone help me with this?