Virtualmin Pro on 2 Servers

HI

I am looking to setup 2 servers with a total of 100 domains (50 per system), both are the same hardware and Centos 5.0, Virtualmin Pro 3.50(50 domain licenses).
And want each server to also act as a secondary MX & DNS for the domains on the other server, will I have any issues with this ?

Thanks

Denis Croombs