How To Intercept VoIP Calls

On the italian website ZeusNews.it there's an article that explain, sketchily, a way to intercept VoIP calls without breaking the cryptographic system but by using bugs of variable bitrate audio compression.

Here's the link:
http://www.zeusnews.it/index.php3?ar=stampa&cod=7778
(English translation by Google)

Have a good reading.