Even i got the same offer letter but with a little difference. The email address is [email protected]. I hope all qatar airways email address has a domain of qatarairways.com. They did not ask me to pay anything. But I think that will be their next steps. Anyways thanks to all of the guys who commented here and a special thanks to the guy who posted this. I'm looking for a job. So I was a bit confused about what to do. Now I got a clear picture. Again, thanks guys.