DSC 4020 with PC4401 DVAC Card

Hello; I have an existing site that has a 4020 installed and is being monitored by DVAC's (PC4401 installed). Another client is moving into the same site as well and would like to have there own security system. The existing client has no problem with sharing the current system with the new client. The decision to add the new client as a partition on to the existing system was chosen. We created a new account for the new client and added it into there respective partition. Unfortunately It appears that the DVAC card can only support one account code from what I could get out of the manual. Any signal I generate on the new partition always comes in on the original account. Has anybody found a way to add two account codes to the 4401 module and get it to match that of the partitions