When someone sends an email message to your domain, the sender's mail server delivers it to the first available server in the priority list.

You create new MX records, or change their priority, in order to change how email is processed for the domain.

You might want to put some other dns entries in there too? Check that the mx records are pointing to rackspace and you should be good to go. If your Name Servers point to Godaddy and your A records point to Rackspace and you purchased the email hosting on godaddy (which it sounds like you did to set up forwarders) then you most likely have the MX records set to something like smtp.(godaddy's mail servers), which just sounds like a complete mess.

Now most people will typically point the NS to Rackspace, then they will manage the DNS on rackspace and have the email hosted on rackspace and then use fowarders in that email system to whatever address you want.

A mail exchange (MX) record identifies a server that handles email messages for your domain.

A domain has one or more MX records listed in priorty order.

Transferring the email server to another host shouldn’t be difficult: just set up the new mailboxes and forwarders, then update the Mail Foundry destination to point to the new host.The customer uses a nice cloud-based email filtering service by Mail Foundry.That means that their MX records point to Mail Foundry, and Mail Foundry subsequently forwards spam- and virus-free email to the on-site server, which is configured to only accept SMTP traffic from the Mail Foundry servers.A Mail Exchanger Record (MX record) is a type of resource record in the Domain Name System that specifies a mail server responsible for accepting email messages on behalf of a recipient's domain, and a preference value used to prioritize mail delivery if multiple mail servers are available.And Example of a MX Record would look like the following (these are servers): You would also need the MX Level and TTL (Time To Live) The above example is of an MX record that is being edited/added to our system. When you purchase a email plan or if you have an existing Domain Account you can setup email with Godaddy.