ICOAT  There is no docu yet, but the answer to your question is

":2006-11-30 sa su, 2006-12-01: tu th sa su"

some other examples:

"" -> no holiday

"su sa" -> all sundays and saturdays are holidays

"2005-02-01" -> the first february 2005 is holiday.

"2005-02-01:" -> each day since first february 2005 (including) is a holiday

":2005-02-01" -> each day before first february 2005 (including) is a holiday

"2001-01-01:2005-12-31" -> each day in this range (including borders) is a holiday

"2001-01-01:2005-12-31 sa su" -> each day in this range which is a sunday or saturday is a holiday

"2001-02-01, sa su" -> the first february 2001 and each saturday and each sunday are holidays.  
(Version 0.05)