I constantly receive feedback emails (about new comments to my blogs) with wrong characters in the e-mail title field. For example:
New comment on your post #150 "Lēts un ērts Excel aizvietojums"
Author : someone (IP: 194.153.xxx.xxx)
E-mail : firstname.lastname@example.org
As you can see in the email body unicode letters are preserved and are shown correctly, but in the Topic (email header) instead of "Lēts un ērts" I see "=22L=C4ts_un_=C4rts"....