Intrusion Detection with Load Balancer behind

Hi everyone,

we have 2 WAN Connections in our Company.

A load balancer in a data center distributes the connections to our 2 WAN Connections.

Now every incoming connection to the PBX has the Same Client IP.

Is there a way to get the PBX find out the real client ip? IDS should not block the IP of the load balancer.
(We use Zen Load Balancer on Debian 8)