the error returned from paypal is:
["ECO_Auth_Result"]=> string(2102) "2010-06-12T14:22:55ZFailure584bf13b41c96Authentication/Authorization FailedYou do not have permissions to make this API call10002Error60.01349298"
or:
Authorization Failed. You do not have permissions to make this API call.
This means there is a problem with your paypal account settings. Contact PayPal Support to determine why you are not being allowed permissions to make the Express Checkout API call.