They are often slow about this, but not that slow. Have you tried contacting Sun?
"We're kind of on the level of crossword puzzle writers... And no one ever goes to them and gives them an award." ~Joe Strummer sscce.org
Joined: Jun 11, 2007
The expected time to receive the certificate is within one month. However they can be a bit late. I got my certificate on the 30th day to be precise.
Have you registered yourself at the sun certification site and checked out whether it is showing as exam passed status against your name. If not, please do so. And then contact responsible people out at Sun.