Version: 4.3 (using 4.3.00 (KDE 4.3.0), Chakra KDE) Compiler: gcc OS: Linux (x86_64) release 2.6.30-ARCH In my case, the lack of this feature means I have to use more than one distribution list to get a mail sent to all intended recipients. So why not replace the radio buttons with checkboxes?
Thank you for your efforts you put into this bug. kab3 has long been deprecated, and so I close its old reports. If this bug/wish is still valid for kab3's successor kaddressbook in any recent version (5.0 or later, as part of KDE Applications 15.08.0 or later), please file a new bug against kaddressbook.