bind configuration issues

[Ray]

Hello,
I am adding a redundant Internet connection to my current hosting setup and I 
need to figure out how to set up the DNS to make this work.
Current setup:
freebsd 7.0 machine, one local IP address, runs web, mail, and name server. 
static ip address in router.
I have two DNS servers registered, but they both point to the same ip address 
an the same machine. (Yes, I should have my fingers slapped.)

Desired setup
same machine, one local IP address, runs web, mail, and name server.
different router (Linksys RV082) with 2 static ip address.

How do I set up bind so that 
1) bandwidth is shared between the two connections,
and 
2) if one goes down, the other keeps working.
I had a few ideas, but they all seem to have flaws.

feel free to answer with links or search keywords.
Thanks
Ray