applying wpautop to metabox textarea


Sorry I am not sure how to use wpautop properly when applying to custom post types meta boxes.

Basically I am using it to save uses having to use <p></p> to add paragraphs to textarea in my meta boxes.

I presume I have to add something to my functions.php file, but I have a number of different types of text area meta boxes, does any one know how to do this or what code is needed?