I'm using the current versions of Aquamacs and orgmode.
Just 30 mins ago, I noticed that it started working after I restarted Aquamacs.
Will try to reproduce this sometime today and forward info to list.

Cheers.
Fil

On 16 January 2011 08:56, Eric S Fraga <e.fraga@ucl.ac.uk> wrote:
"Filippo A. Salustri" <salustri@ryerson.ca> writes:

> So, I'm looking at my global todo agenda, and I'd like to change the state
> of the task under the cursor.
> According to the doc, 't' should let me do that, but when I hit 't', I get
>
>> wrong type argument: stringp, nil
>
> which isn't really doing it for me as an explanation of what I'm doing
> wrong.
>
> Thoughts anyone?
> Cheers.
> Fil

Works for me just fine.  What versions of org and emacs are you using?
What is the value of org-todo-keywords?  What is the actual entry you
are trying to update?

You may wish to "M-x toggle-debug-on-error RET" to get a backtrace to
see if that gives any hints.
--
: Eric S Fraga (GnuPG: 0xC89193D8FFFCF67D) in Emacs 24.0.50.1
: using Org-mode version 7.4 (release_7.4.199.g8be1.dirty)



--
Filippo A. Salustri, Ph.D., P.Eng.
Mechanical and Industrial Engineering
Ryerson University
350 Victoria St, Toronto, ON
M5B 2K3, Canada
Tel: 416/979-5000 ext 7749
Fax: 416/979-5265
Email: salustri@ryerson.ca
http://deseng.ryerson.ca/~fil/