Despite un-checking the "Reopen windows when logging back in" checkbox when turning off the computer, applications reopen sometimes at the next start-up. Furthermore, this happens also when I quit all the applications manualy before, which is strange. This issue occurs in Mountain Lion (10.8, 10.8.1 and 10.8.2), never actually happend to me in Lion. Maybe it's worth noting that this is not a clean install, but an upgrade from Lion.
Is there any solution how to prevent this (maybe from the Terminal)?