MX record ordering

[lawrence.a.kravets at us.arthurandersen.com]

We have recently upgrade to Bind 9.1.0 from Bind 4.9.3. Given the following, we
have reason to believe that the order of response of the following has changed.
We expect that it would split equally between server1 and server2.
Unfortunately we see more traffic on server1 than server2.  Has something
changed in Bind 9?

mailhosts      IN   MX   10   server1.zone.com.
mailhosts      IN   MX   10   server2.zone.com.
mailhosts      IN   MX   20   server3.zone.com.
mailhosts      IN   MX   30   server4.zone.com.


Thanks,
Larry Kravets

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