Can forwarders list really work?

[Igor Shabaltas]

Hi Folks,

There is a network with two internet connections: to ISP-1 and to ISP-2.
There are three name servers (Bind-8.2.2p7) - one 'internal' and two
'external'.
Internal DNS server (IP 10.x.x.x) has next options:
...
forward only;
forwarders { isp.1.sub.ip; isp.2.sub.ip; };
...

Where:
isp.1.sub.ip - real IP address of DNS server in subnetwork connected to
ISP-1
isp.2.sub.ip - real IP address of DNS server in subnetwork connected to
ISP-2

All requests from internal network are going to internal DNS server.
The aim: when any one connection to internet is down, DNS requests will be
resolved succesfully through other one.

Good idea?
What we have in reality?

If ISP-2 is down all still work perfectly.
If ISP-1 is down you can resolve your request, but it takes a long time. As
a rule you need to make three or four requests to get correct answer.
So, only first IP in forwarders list is actually useful.

How is it possible to deside this  problem and make this scheme alive?

May be in the next versions of Bind we can have an option like 'forward only
parallel'  to make the parallel requests to all forwarders at the same time?
Why not? :-)
Or is it just my fault and I forgot to include some options? Help!

Any suggestions, comments?

Thanks in advance,
--
Igor Shabaltas