thanks for the reply.
the problem is that i don't host my domain in DH, so i need to point the sub-domain to an IP to make it work.
for instance i used the same ip that i used for a wp blog i host here (which is working). in that case i'm using a subdomain something like this: mysqlwp.domain.com
"mysqlwp" is added as a subdomain in my dns manager and it points to 184.108.40.206
i'm using the same IP for this other domain but it's not working.
hope i made myself clear.