3Com 3032 Configuration Manual page 247

Fault Diagnosis and Troubleshooting of X.25 243
If receiving the ping packet forwarded from the router at one end, check
whether the returning route has been configured in the routing table. In
addition, if the destination IP address for returning the packets is different from
that configured in the Frame Relay address map and X.25 address map, you
need to reconfigure the maps.
If multiple X.25 address maps for reaching the same destination X.121 address
have been configured in an X.25 template, check whether the
x25
command has been configured so that multiple X.25 SVC calls
vc-per-map
can be placed with the same X.25 address map. Use the
debugging x25
command to debug the X.25 protocol.