Allowing styling of “et al.” has been discussed before, but as far as I
could discover it hasn’t yet been implemented.
Previous discussion:
http://sourceforge.net/mailarchive/message.php?msg_id=D3FF8DEC-EA31-46A4-80B5-7F2F570CC864%40gmail.com
New tracker ticket:
http://sourceforge.net/tracker/index.php?func=detail&aid=2176252&group_id=117435&atid=678021
Rintze Zelle