From [1] MSNBC, with thanks to Jeff Lastname:

An Internet posting obtained by NBC News — written mostly in Arabic — details how to fire a shoulder-fired missile and how to overcome security measures.

NBC terrorism analyst Evan Kohlmann says it was posted five days ago on an Internet location used by Iraq's top terrorist, Abu Musab al-Zarqawi.

"We've seen plenty of material on radical Islamic Web sites dealing with shooting down military aircraft in combat zones," says Kohlmann. "However, this is the first time I've ever seen the deliberate targeting of civilian aircraft leaving U.S. airports."