[Freeswitch-users] [freeswitch-users] Grandstream ATA configuration

Has anyone interfaced Freeswitch with any of the Grandstream ATAs? If so, are there any issues that a user needs to be aware of, prior to install? I have a customer who is installing Freeswitch with a Grandstream ATA and interfacing that to an Avaya PBX. Any heads up on potential issues would be greatly appreciated. Jonathan