For sender, idea is to add 2 user preferences :
SentEmailFromDisplayNameType : list with 3 values (0-Nothing ; 1-UserName ; 2-Text)
SentEmailFromDisplayName : text displays when SentEmailFromDisplayNameType = 2
For recipients, it will depends on the content of AD_User.EMail ;
-> If you want to use personal in email as sender - then you fill your user email as "Nicolas <nmi...@mailserver.com>"
-> If you don't want it, then as usual just "nmi...@mailserver.com"