A couple of months ago Joerg Ziercke of German BKA already told journalists that despite all their efforts, German police is unable to decrypt Skype traffic (and Skype don't rush to cooperate either), so the only option available to them is to intercept calls before they are encrypted or after they are decrypted. That was a pretty clear indication of a MITM'ing police trojan underway.
http://www.reuters.com/article/technologyNews/idUSL21173920071122

I gather this text might make some corporate security managers sweetening like there is no tomorrow