Allow !site token in forward_instructions and forward_thankyou messages

How about forward_instructions and forward_thankyou have the same flexibility as the email messages of using !site. This allows forward to work seamlessly with domain_access which operates multiple websites through one database install. It looks like forward instructions would simply need to have ", array('!site' => variable_get('site_name', 'drupal'))" added to the t() that encloses the message and forward_thankyou would just need to add a t() with the same array. !name might also be useful with thankyou. It just seems like a quick fix that adds flexibility without adding undue overhead or weight.