Comment 4 for bug 855793

I'm afraid this has been hastily reassigned, there's no data in the bug log to decide where the problem is. There's no proof that dpkg is blocking and I'm quite sure it doesn't. However one of the packages that you are trying to install might well try to interact with you on the terminal and if you don't answer, the whole upgrade might block. You need to provide some log files like /var/log/dpkg.log and/or the muon log file (is it apt-based too? so maybe /var/log/apt/history.log and /var/log/apt/term.log).