Correct classes for WordPress menu items

I have been trying to get the current menu item to my custom post types. I cannot get it to work, and when looking at my menu, I am wondering, that if everything is allright.

Which are the correct classes WordPress should generate, when displaying pages, archives and custom post types?

I have this link explaning them: http://ift.tt/1I420dL

But my page for example has the following classes:

menu-item menu-item-type-post_type menu-item-object-page current-menu-item page_item page-item-146 current_page_item menu-item-147

And my custom post type:

menu-item menu-item-type-taxonomy menu-item-object-category menu-item-187

Which seems strange, since the menu is a link to the category and archive page, not a taxonomy?

Thanks in advance