Confirmed. An official of the Syariah Department at Takaful Malaysia has confirmed issuing an e-mail discouraging the Muslim staff of the public-listed company from wishing its customers "Happy Deepavali" as it was against the syariat. Attempts to get the CEO of Takaful to comment on the mail, however, were unsuccessful.
Walsk69 broke the story after receiving a copy of the mail on Friday and alerted this blogger. Neither of us mentioned the company's name then for fear that the e-mail had not come from Takaful.
[note: this is an update. pls leave comments, if any, under original posting No More Happy Deepavali?]