KMail and group emailing

Using Suse 7.3 and Kmail 1.3.1, is there a way to set up the addresws book so and enitire group can be emailed at one time? I need to be able to send the same email to over 50 people on occasion, but I can't figure out how to do groups, other than create a "Group address file with all 5o addresses listed (a lot of duplication). Any ideas? Harry G