MX problem

[Roman Rodionov]

Hello all!

I had set up our domain's BIND but I couldn't receive mail messages. My ns and mail server are same computer. This is my zone file:
@                       IN      SOA     ns.cases.ru.    rodionov.cases.ru.
(                        1997081501  ; serial number
                        28800       ; refresh
                        7200        ; retry
                        604800      ; expire
                        86400     ) ; minimum TTL

                        IN      NS      ns.cases.ru.
                        IN      NS      ns1.aha.ru.

localhost               IN      A       127.0.0.1

ns                      IN      A       195.2.85.210
@                       IN      MX      1 ns
www                     IN      CNAME   ns

I also set PTR record:   210.85.2.195.in-addr.arpa.    IN      PTR     ns.cases.ru.

What I'm doing wrong?

Thanks in advance, Roman Rodionov.