Version:           1.9.6 (enterprise 0.20070907.709405) (using KDE 3.5.8, Kubuntu (gutsy) 4:3.5.8-0ubuntu3.1)
Compiler:          Target: i486-linux-gnu
OS:                Linux (i686) release 2.6.22-14-generic

When creating a new eMail, I enter the first few characters of the recipients name, I get some suggestions from my KAddressBook, everything fine up to here.
When I scroll through the suggestions to choose the right one, in the "To:"-Field appears not only 

"surname, name <name@domain>"

but something like 

"othersurname "surname, name <name@domain>",

where othersurname is the name of another person in the list. This happens on and on. So you might get something like

"Jones "Smith "Meier "John Doe <john@doe.com>"

So i think, there's something wrong when filling the To-Field, maybe the String containing the recipient is not filled properly, or the To-Field is not cleared properly...