[support] cck filefield / image upload

[luca capra]

Hi,

I'm using hook_form_alter to present a special node form to anonymous 
users in D6.

I've got unlimited upload for a cck image field, but I would to limit to 
1 for unauthenticated user.

I've found this un-answered question in the cck issue queue:
http://drupal.org/node/530828#comment-2288010

Can somebody point me to the right hook or a similar implementation (eg. 
fork the image widget) ?

Thanks in advice,
Luca