A method, a system and a computer program product of transmitting availability information in an electronic mail system are disclosed. The system includes a first system including a sender, the first system is adapted to activate an availability indicator having a start date, wherein the activation is performed by the sender and extract availability indicator metadata from the availability indicator. The availability indicator metadata includes the start date, an end date, and at least one availability indicator message. If an e-mail has not been sent to a receiver since activation and if a current date is prior to the start date, the first system is further adapted to attach the availability indicator metadata to the e-mail, and send the e-mail to the receiver. The electronic mail system further includes a scheduling system functionally coupled to the first system, and is adapted to define the availability indicator.