This is also a problem with earlier versions
Steps to reproduce:
1.) Open a message
2.) Select Tools\Add Sender/Receipients to Address Book from the Action buttons
3.) Select one or more entries from the Available Addresses section that are commented with the quoted name seperated by a "," (example "Harris, Sean" ) and click on Add Address.
4.) It will split all the addresses that have a "," in them into two addresses, and none of them will added to the Add Address section.
5.) If you use the Add All button, it will add all the addresses to the Add Address section, but for each address that has a "," it will add two entries into the Add Address section.
It seems that the "," is being seen as a delimiter, and creating a second address.