Wow 2 pets already...I guess you do have your hands full!

You could try posting about the cat on some other websites as well. Try this one out :
http://www.qaws.org/lostfound/lostandfound.php

I saw a cat just like this one at the Doha Gulf Club just a few days ago. Also very friendly and loving; unlikely it's the same cat though, as Al-Sadd isn't anywhere near the club.

Do let us know on the forum when if and when you're able to find the owners; I'd love to hear about a happy ending !