You must register to receive your free admission!

http://disneyland.disney.go.com/disn...OYBLandingPage

You get free admission on your birthday to your choice of Disneyland or Disneyworld in 2009.
From the registration webpage:
If you haven't yet signed up for free admission to a Theme Park on your birthday, register now. If you're already registered, just log in to your account.

To qualify to register online for free Theme Park admission on your birthday, you must be:
* 13 or older to register yourself
* 18 or older to register your children
* A U.S. or Canadian resident

Show valid ID with Date of Birth at Disneyland® Resort.


Other info from the pages:
To get this wonderful birthday gift for yourself or your children, follow these simple steps:

Register yourself—and your children too, if you want.
Print the reminder email with its confirmation message that you will receive 2 weeks prior to your birthday to redeem free admission on your birthday in 2009.
Bring proper ID and your confirmation message to the Main Entrance ticket booths outside the Disneyland® Resort Theme Parks.
If you are an Annual Passholder or already have a Multi-Day ticket you will use on your birthday, go ahead and register and bring the free admission on your birthday confirmation and proper ID to the ticket booth so you can choose from one of our other exciting birthday gifts instead.

Here is what the "alternate" gifts are:

A birthday fun card in an amount equal to the price of a 1-day One Day/One Park base ticket* for you to use on your birthday for merchandise, recreation or fun activities at select participating locations at Disneyland® Resort; or
A special birthday FASTPASS® ticket+ for certain attractions at the Theme Park you visit on your birthday; or
A 1-day One Day/One Park base ticket for you to use any time until your next birthday.