Most that know have signed to not reveal, and indeed are under criminal legal restraint from answering.
Even public domain - because it was noted in another countries press - facts are not to be repeated by those folks.
Howver on the simple question of monitoring your calls - the answer is yes - but the method is by computer phrase capture. This is not a tap on "your call" - it just checks phone, etc. traffic for key phrases that may indicate evil intent.
Last I looked the operation was in Toronto (why outside the US I do not know) and was a simple record, review, and see if supervisor wants to have agent do some real monitoring of a real person that said the phrase. Low level military work the desks -
A similiar program for the internet - called carnivore - has been proposed and has discussions all over the media/internet.
http://www.free-market.net/spotlight/carnivore/http://archive.aclu.org/news/2001/w021401b.htmlhttp://www.wired.com/news/politics/0,1283,46852,00.htmlhttp://www.epic.org/privacy/carnivore/http://www.internetnews.com/bus-news/article.php/1146651http://www.fbi.gov/congress/congress00/kerr072400.htmhttp://www.crypto.com/papers/opentap.html