opensmppbox smsc-route

Hello,

I have installed kannel with opensmmbox, all work fine.

I have connected 3 different ESME customers on opensmppbox, 
and I need for each ESME have additional sms routing to separate SMSC on kannel server. 

With this configuration all sms from all ESME (customer1,customer2, customer3) route to smsc1.
But I need to have route like

from customer1 to smsc1
from customer2 to smsc2
from customer3 to smsc3

Please help.

===================
smpplogins.txt
customer1 password1 localbox *.*.*.*
customer2 password2 localbox *.*.*.* 
customer3 password3 localbox *.*.*.* 

opensmmpbox.conf
# sample opensmppbox.conf

group = core
dlr-storage = mysql

group = opensmppbox
opensmppbox-id = mycompany
opensmppbox-port = 2799
bearerbox-host = localhost
bearerbox-port = 13005
log-level = 0
log-file = "/var/log/kannel/opensmppbox.log"
our-system-id = mycompany
route-to-smsc = smsc1
smpp-logins = "/etc/kannel/smpplogins.txt"
use-systemid-as-smsboxid = true

# the following is just standard dlr configuration

group = mysql-connection
id = dlr
host = localhost
username = kannel 
password = kannelpass
database = kannel

group = dlr-db
id = dlr
table = dlr
field-smsc = smsc
field-timestamp = ts
field-destination = destination
field-source = source
field-service = service
field-url = url
field-mask = mask
field-status = status
field-boxc-id = boxc 


BR,
Alekxandr