Issabel Call Center Setup

Dear All, We are in the midst of the setting up a call centre. The hardware installation is complete. We are running 2 ISSABEL install on two server and they are configured as high availability active /passive mode. The problem is the call center module. When we install the module, the agent login facility is not working as per configuration. We have created agent, campaign, list and form but the agent still cannot log in. If you have experience in Elastix call center, please submit your proposal