By some coincidence, I just received this from Jonny and Annie Rosen of Annie and the Hedonists. Jacqui Steiner, who co wrote the MTA song with Bess Lomax Hawes gave a workshop at the Pick'n' and Sing'n' Gather'n's Gottagetgon festival in 2009. The song has quite a radical background, as described in the Boston Globe this past Sunday. Sorry, maybe someone can make two "blue clickies" for these links.
http://www.boston.com/news/local/massachusetts/articles/2010/12/26/charlies_true_history_moves_out_from_the_underground/


And another article as well:

http://www.dissentmagazine.org/article/?article=1167