ap_user_can_ask() function is not active

Hi,

This is very nice and i’d love to use it to my blog.
But, i have a question about function that not active : ap_user_can_ask()
when this is not active ask form will be showing and unregistered user don’t know about login.
or i’ve missed where is ap_user_can_ask() function ?

Thanks, i hope you understand with my limited english .
ivo