Cluster Asterisk servers/ sip proxy on thirdlane multi-tenant pbx

I would like to get Thirdlane multi tenant pbx to work on a sip proxy and that it uses load balancing module to use mutiple asterisk machines doesnt matter if its vm's or physical either. there will be a requirement for load testing for number of concurrent calls too but thats if we can do it. only serious asterisk professionals please.. thanks