Look in some very old English carol books and you will see "4 colly birds," not "4 calling birds." The word "colly," meaning "black," is not well known in America.
Check out:
http://www.snopes.com/holidays/christmas/12days.asp
The snopes response was redictable. I appreciate the response though. Even if it is just a story, as a Catholic and a Christian, the parrallel to today's on going persecution of Christinity in this country is worth considering. Someday we may all be practicing our faith in secret if the Left has their way.