[USR-TC] Problem with Protocol type?

Hello ... when i do a "list session" I am noticing alot of customers listed as "UNKNOWN" in the protocol type field ... some are showing as PPP but they all should be ... any ideas what is wrong?? HiPer>> list sess SESSIONS Name Conn_Type Prot_Type EBJ WAN UNKNOWN bnk WAN UNKNOWN cra WAN UNKNOWN jlm WAN UNKNOWN rmw WAN PPP Pyke WAN UNKNOWN cars WAN UNKNOWN daja WAN UNKNOWN dove WAN UNKNOWN