While it should default to a sane value, make sure the cookie path and domain is set "correctly". Usually you'd want it to be "/" (root of domain) and your domain name without www, so it's readable with and without www.

I don't think you can read the encrypted cookies with Javascript. It would mean you would have the key on the client side and have the same decryption algorithm, but that wouldn't be safe as your key would be visible for anyone.

Hi guys and thanks for answers,

Actually, purpose of this is not to read content of the cookie, but to read expire date of the cookie (it contains an oauth token). Encryption is also set on this expires value ?