Problems in receiving emails to Multiple Domains.

[Ashok S (SSD-MDSRO-SIP)]

HI,


We have a domain mycompany.com, and we have various subdomains under it like
abc.mycompany.com, def.mycompany.com, ghi.mycompany.com.  Each  subdomain
has a messaging server in the same name.  The service provider hosts the dns
server.  We would like to have a email address as
username at subdomain.mycompany.com and we would like to have abc.mycompany.com
as our mail exchanger for the domains (abc,  def,  ghi ).  Please explain
the associate DNS records.

Any help is welcome. Thanks in advance.

Regards,
S Ashok