you mentioned all other routers are running in bridging-mode. i was wondering whether the 837 is configured in bridging-mode as well.
below is the sample config for 837 running in bridging-mode:
Current configuration : 907 bytes
!
version 12.3
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname 837rt
!
enable secret 5 xxxxxxxx
enable password xxxxxxxx
!
no aaa new-model
ip subnet-zero
no ip routing
ip domain name yourcompany.com
!
ip audit notify log
ip audit po max-events 100
ip ssh break-string
no ftp-server write-enable
!
!
!
!
!
!
interface Ethernet0
no ip address
no ip route-cache
bridge-group 1
hold-queue 100 out
!
interface ATM0
no ip address
no ip route-cache
no atm ilmi-keepalive
pvc 8/35
encapsulation aal5snap
!
dsl operating-mode auto
dsl power-cutback 0
bridge-group 1
!
ip classless
no ip http server
no ip http secure-server
!
bridge 1 protocol ieee
!
line con 0
no modem enable
transport preferred all
transport output all
line aux 0
line vty 0 4
!
scheduler max-task-time 5000
!
end
837rt#
one point needs to be noticed is that after applying these code, remote access such as telnet or ssh will not be able to establish to the router. console is the only option.