I created a distribution list (or contact group) from an email with multiple recipients. Later I found out that the addresses used in that list had been duplicated. When deleting the duplicated addresses, the list complains that the contact is no longer there. 
This problem does not occur with distribution lists created from within kaddressbook. 

Reproducible: Always

Steps to Reproduce:
1. open or create an email in kmail with multiple recipients
2. Click "Save list", name it and save it.
3.
Actual Results:  
Duplicate adresses are generated for each name in the list.

Expected Results:  
The list should use contacts already there.