allowed tags in gift certificate

Hi, what are the allowed tags in the gift certificate email text? I can see {gift_certificates} and {website}, but is something like {first_name} possible too?

List of dynamically populated variables
{gift_certificates} - the gift certificate codes generated for the customer
{website} - the store owner's website
{user_first_name} - the customer's first name
{user_last_name} - the customer's last name

This list can be found in the documentation, user_guide.html