In a theme I have created several months ago I have created a custom post type called "Portfolio" and now I am having problems with this with the 3.1 RC3.
Now on some places within the theme this post type is not recognized as a valid post type, for example when adding new meta boxes to the post:
add_meta_box( 'new-meta-post-boxes', 'Additional Settings', 'new_meta_post_boxes', 'Portfolio', 'normal', 'high' );
the code above works fine with the previous versions, but with this version I have to insert 'portfolio' instead of 'Portfolio'.
I realize now that partly this might be my mistake, maybe because I got a bit confused of the documentation:
(string) (required) Post type. (max. 20 characters)
saying that the default post type is "None" with an uppercase letter.
However the theme I have created is already used by lots of users and an update to the version 3.1 will break some of the theme functionality.
Therefore I will be happy if this problem doesn't exist in the 3.1 version or maybe if someone suggest a code change that can be done on one place only, rather having to edit the theme on all the places "Portfolio" is used.