Question about the Zhevra Mount

OK, so as it happens I was going to be referring a friend today anyways (good luck for me).

BUT What I'm wondering is once he pays for his second month of play time, and I get the Zhevra mount credit on my account, do I have to use it on a character that's present on the account when I get the credit? Or will I be able to gift it to my Death Knight once I have WotLK?

response to this would be great,

Cheers!