It's added on March 23 on Azzam. But I also saw it on another islamic site. I am searching for it, but I can't remember where. It was also on Azzams old webspace, so I guess it was from last year. Also it was posted on the Ummah News forum, but removed, so I cannot give the exact date.
Azzam is a Britian based publisher of armed jihad related articles, books and video tapes.
Some more about another publisher can be found here:
AN EVENING IN FRONT OF THE TV: JIHAD (ISLAM CALL FOR JIHAD MUST READ)