[support] Drupal 6.10 autocomplete ignored in hook_user() register?

[Doug]

On Wed, 19 May 2010, Earnie Boyd wrote:
> Doug wrote:
> > This is a bit obscure but...
> >
> > I'm trying to alter the new user registration form in my
> > modules hook_user() function in order to get users to
> > select a unique short identifier (e.g. initials).
> >
> > Although I add the '#autocomplete_path' =>  'module/autocomplete/charid'
> > to the form textfield element, it is not activated.
>
> Do you have a MENU_CALLBACK defined for the path and a function to give
> the values for the auto completion?
>

Yes. 
And it works fine when called via hook_user($op='form',...),
it just doesn't work when called via $op='register'.