[Remops] why does dingo have two mx hosts with the same IP?

[Anonymous via the Cypherpunks Tonga Remailer]

$ dig mx dingoremailer.com
...
;; ANSWER SECTION:
dingoremailer.com.      6559    IN      MX      0 smtp.dingoremailer.com.
dingoremailer.com.      6559    IN      MX      0 mail.dingoremailer.com.

;; ADDITIONAL SECTION:
mail.dingoremailer.com. 6559    IN      A       208.180.124.28
smtp.dingoremailer.com. 6559    IN      A       208.180.124.28

?!?