Hi Rick,
We use cookies only for login and roles (which can be considered part of login). According to the article you posted this is ok:
The law allows an exception for "strictly necessary" cookies, such as those used to remember when something has been added to a shopping basket. These cookies would be expected by the user implicitly for the action they requested to be carried out. Another example would be login.
The article also state that the law only applies to organizations that have a business presence in the legal jurisdiction of the EU.
Unless you are using cookies for other purposes in custom features I would say that organizations using mojoPortal will be in compliance with the law.
The only things that might bear further scrutiny is 3rd party services that may also set cookies, google ads may use cookies I'm not sure. The add this button does use cookies so people may have to choose not to use that. Facebook like button requires users to be logged into facebook to like something, that requires a cookie I'm sure but also falls into the login category that is allowed without a prompt.
The coming release of mojoPortal will also have a new feature for putting extra content on the login page so the overzealous worriers could put a message there indicating that logging in does require use of cookies.
Best,
Joe