Thursday 3 Feb Chinese New Year
Tueday 15 Feb Birth of the Prophet Muhammad SAW
Friday 22 Apr Good Friday
Tuesday 17 May Birth of Buddha 2555 (Vesak Day)
Thursday 2 June Asscension Day of Jesus Christ
Wednesday 29 June Isra' Mi'raj of the prophet Muhammad SAW
Wednesday 17 Aug The Independence Day of Indonesia
Monday 29 Aug Public Holiday (Commemoration of Ied ul-Fitr 1432 H)
Tuesday 30 Aug Ied ul-Fitr 1 - 2 Shawwal 1432 H
Wednesday 31 Aug Ied ul-Fitr 1 - 2 Shawwal 1432 H
Thursday 1 Sep Public Holiday (Commemoration of Ied ul-Fitr 1432 H)
Friday 2 Sep Public Holiday (Commemoration of Ied ul-Fitr 1432 H)
Monday 26 Dec Public Holiday (Commemoration of Christmas Day)
Note: New Year (1 January 2011), Hindu Saka New Year 1933 (5 March 2011), Eid ul-Adha 1432 H (6 November 2011), Islamic New Year 1433 H (27 November 2011), and Christmas (25 December 2011) Holidays are not mentioned in the above list because they fall on Saturday or Sunday.
Source: http://www2.idx.co.id/MainMenu/Trading/TradingHoliday/tabid/85/lang/en-US/language/id-ID/Default.aspx