In the 0.4 series we can only send a message to the user that an unsigned package has been installed. There is no confirmation possible. I will implement this in the next days.
From 0.5 on it is possible to ask for confirmation before installing untrusted packages. But packagekit 0.5 depends on policykit-1. It is open when we will see required kpackagekit and kde policykit support.
In the 0.4 series we can only send a message to the user that an unsigned package has been installed. There is no confirmation possible. I will implement this in the next days.
From 0.5 on it is possible to ask for confirmation before installing untrusted packages. But packagekit 0.5 depends on policykit-1. It is open when we will see required kpackagekit and kde policykit support.