Comment 1 for bug 132456

Further research has led me to find the cause of this behaviour. It is not a duplicate of bug 87023 as suggested by your email, it is a new and extremely serious bug that will compromise any computer affected with it. Its cause is the package 'kdesudo 1.1.0Ubuntu1'. When this package is removed the default behaviour returns and passwords are requested for every instance of root or admin access. This is how it should be. I suggest you look at this package carefully.