Confusing info in MSDN on what type of encryption is used for cookies?

Here it says 3DES is used for cookie encryption when protection ="ALL" is used for Form Cookies:

http://msdn.microsoft.com/en-us/library/1d3t3c61(VS.80).aspx

Here it says AES can be used with Role Cookies :

http://msdn.microsoft.com/en-us/library/ms998288.aspx#paght000007_rolecookies

If I add the machines keys as noted to web.config file and use an AES Key for decryption what encryption will be used in the first case for Forms cookies?

 
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