I don't believe what happened to me this night.
I finally managed to run update to Plesk 10.1.1. After it was done, my Apache stopped to work. All my sites gone down. I paid for chat support $15, no body answered for 2 hours... Hours are passing... I have websites with thousands of clients...
I was desperate... Then I found info on the net there was a bug in the latest version of Plesk (?!) and that I must upgrade PHP....
You guys really don't care about your clients. I will be looking to change Plesk for cPanel or anything else as soon as possible.