[exim] Outgoing emails with diferent IP addresses

Hi,

Here is my problem, I need to send emails to some domains with some IP addresses. For example I have 3 files with several ip addresses each one.

File 1              File 2               File 3
192.168.0.1         192.168.1.1          192.168.2.1
192.168.0.2         192.168.1.2          192.168.2.2
192.168.0.3         192.168.1.3          192.168.2.3
192.168.0.4         192.168.1.4          192.168.2.4
192.168.0.5         192.168.1.5          192.168.2.5
...                 ...                  ...

When exim process an outgoing email, needs to check for some header, for example X-GROUP-1, to determine wich group/file of IP addresses needs to use, I use a perl script that returns a random IP address of a given file as parameter. Exim recive the emails from an aplication that can put any required header if I need it.

I'm pretty new to exim, and I don't know how can I do it, can anyone help me?

--
Ezequiel M. Cardinali
I.T.I Linux