Question : DNS, MX Record, Mail Server, how to get it working

I am having trouble setting up my A, CNAME and MX records for a domain.
I have the mail server on one IP and the web server on another. I have the records working for the web server, domainname.com (A record) and www. (CNAME). I just can't work out how to get the mail working. My host allows me to setup A, CNAME, AAAA and add free text to a record (whatever that is).
I have MDaemon mail server and previously I've just collected mail from the host, but this time I want the mail server to accept the incoming mail for this domain.
I thought I was OK when I set up another A record mail.domainname.com and then pointed the created the MX that pointed to mail.domainname, but then mail for domainname.com didn't go anywhere. I know that somehow I've got to associate the MX with the right A record, but when I want the mail and web site traffic to go to different IP addresses I get stuck.
Thanks for any help.

Answer : DNS, MX Record, Mail Server, how to get it working

well, the 'mail.' has no relevance on what domain is actually being used there, its just a name to point at for mx records.

when sending an email to your domain, such as domain.com

A recipient mail server will do an mx lookup on domain.com and find mx records for it. these mx records will point at mail.domain.com as the server for the 'domain.com' mail server.

If you were to were going to set up mx records for mail.domain.com, you would have something like 'mx1.mail.domain.com' as your mx records for that domain and so forth.