I'm using Emacs org-mode's agenda feature.
When I put a timestamp on an item in my gtd.org file, with C-c . , it will show up in my agenda for the week. The date is in this format: <2011-12-25 Sun>
If I use M-x holidays to get a list of holidays, the dates are in this format: Sunday, December 25, 2011: Christmas
How can I add holidays to my gtd.org file, in a format that shows up in the agenda?
I've looked through the Emacs manual and the org-mode manual, for either a way to change the date formats in 'holidays', or a way to convert a date into org-mode's format.