Okay, I found this, but it still doesn't explain the "his" :
 
The horse was called Freyfaxi, Freyr after his godly owner, and Faxi is a common name for horses (meaning eye-catching mane).
----- Original Message -----
From: Laurel Bradshaw
To: norse_course@yahoogroups.com
Sent: Sunday, October 19, 2003 1:57 PM
Subject: Re: [norse_course] Hrafnkel 47-73 / Laurel -- question

It might make more sense to me if I knew what "faxi" translates as.  Anyone?
 
Laurel