PolicyKit

blueman uses PolicyKit to manage users' authenticatication as root to use some of its features. Most GNU/Linux distributors will want to create a PolicyKit rule to avoid their users having to enter the root password over and over. Below is an example rules file which on most distribution will need to be placed in /etc/polkit-1/rules.d/. Some distribution may not use the wheel group so make sure to replace that with whatever is appropriate.

/* Allow users in wheel group to use blueman feature requiring root without authentication */
polkit.addRule(function(action, subject) {
    if ((action.id == "org.blueman.network.setup" ||
         action.id == "org.blueman.dhcp.client" ||
         action.id == "org.blueman.rfkill.setstate" ||
         action.id == "org.blueman.pppd.pppconnect") &&
        subject.isInGroup("wheel")) {
        return polkit.Result.YES;
    }
});