For offices outside Delhi / New Delhi, the Central Government Employees Welfare Coordination Committees at the State Capitals are authorised to change the date of holiday, in respect of Idu'l Fitr, Idu1 Zuha, Muharram and Id-e-Milad, if necessary, depending upon sighting of the Moon,if necessary, based on the decision of the concerned State Governments / Union Territories, in respect of Idu1 Fitr, Idu1 Zuha, Muharram and Id-e-Milad.
Now, Central Government Employees Welfare Coordination Committee, Tamilnadu, has issued order dated 31.08.2010 to this effect which can be downloaded from the link below.
ORIGINAL COPY
SOURCE.gconnect