The AV Herald reports that "a Swiss Airlines Airbus A319-100, registration HB-IPT performing flight LX-1311 from St. Peterburg (Russia) to Zurich (Switzerland) with 123 passengers and 5 crew, was climbing out of Saint Peterburg's Pulkovo Airport, when the crew reported engine (CFM56) vibrations prompting them to return to Pulkovo Airport. The airplane landed safely 40 minutes after departure."
http://avherald.com/h?article=425911ab&opt=0

The cause of the vibrations was a multiple bird strike: unlike the famous US Air A320 a year ago, this plane did not experience complete loss of thrust or engine failure.

There are ATC recordings available on Radioscanner.ru. I have also edited these recordings and tried to subtitle them: http://www.youtube.com/watch?v=lICb8p9SvvM . They are interesting to listen to.