Currently on 3.1 with 8720's upgrading to 5.2. We also have an old Center Stage Switch with dual connectivity to campus EPN's via IPSI and Packet Interface boards. Initial meeting with vendor they told us that the remote EPN's need a T1 for a sync source for analog modem and fax lines. 5.2 does not support Packet Interface and all campus EPN's will use IPSI connectivity only. All T1's are located in our main bldg. We have no T1's in remote EPN's that could be used as a sync source. Vendor stated that codecs are not robust enough to support analog over IPSI. Has anyone ran into this? thanks