I would like to create a mailing group. However, the button 'New group' in KAddressBook is not active. I tried to select some addresses that I want to combine in a group. Bit even that doesn't render the button active. I finally found a 'work around' by starting a new composer in kmail, selected the address and then 'Save list'. Surely that's not the way it should be done. What am I doing wrong? Btw, 'Nepomuk' is running, KDE 4.11.5

This is a quite old release: I just tested on Applications 15.04, and "New group" works. What distribution are you using?