Nope, it's an honor system kind of thing! But beyond a million happy birthday greetings from CM's everywhere, no birthday magic is guaranteed. A regular-ish perk seems to be a free dessert cupcake with a candle in table service restaurants but that is not guaranteed and is likely the server's choice.
There are a few threads on here about making birthdays special, you might be able to search for them. Some of my favorite ideas were to decorate your hotel room before the birthday person checks in, order a cake from Disney's catering department to be delivered to a table service restaurant, and letting the birthday person schedule the day's events and pick out a gift from the parks.
Have fun planning!