The RTMP URL is: rtmp://fms.scctv.net/annenberg/&file=/vod/world_of_chemistry_01.flv
The captions are stored at: "http://cc.learner.org/world_of_chemistry_01.xml"
I have not figured out which parameters
rtmpdump actually requires.
rtmpdump -r <URL> does not work because it's using the wrong value for the "application".
I got these links from "http://www.learner.org/vod/vod_window.html?pid=793"