Comment 6 for bug 208112

I'm not sure by any means but I'm informed that the driver manager should be able to check to see what is installed and what is available with out needing to lock the database. Whether this is actually what it does is question for the developers of restricted drivers manager.

Another thing that could have a caused a lock is a second instance of synaptic/apt-get/dpkg running at the same time but I'm assuming that's not the case or you'd have noticed.