Dear Doop

If it is only because this person has sent the mail to senior executives that he has been terminated, then by all means it is unfair. At the most, there should have been a censure and nothing else (although I still do not see why since its only an introductory mail!).
A lot of companies have a policy of sending introductory mails for every new recruit and there is usually a designated person and a format to do so. If TCL has none and if it is against company policy to send such mails (again I see no reason why, but if its the policy then so be it) then he should have been made aware of it but it certainly does not merit a termination.
Personally, if I am able to help this person out in any way I would be glad to, so if you can forward his details to me I might be able to do something. Again, this is purely on the premise that the incident has happened exactly as you have stated and there are no other facts in this.
Thanks
Paresh