The 2nd generation Dual T1 NIM (1202872L1) should work fine in the 3rd generation 3205. Obviously, you need to configure the routers in order to use the NIM(s).
The following example is using a PPP interface with it's own IP address to use for routing. You can also use bridging instead, but I'm just used to doing it this way.
I hope this works.
This is an example of the configuration:
Router A:
====================================
!
interface t1 1/1
tdm-group 1 timeslots 1-24 speed 64
no shutdown
!
interface t1 1/2
tdm-group 1 timeslots 1-24 speed 64
no shutdown
!
interface ppp 1
ip address 172.16.1.5 255.255.255.252
ppp multilink
no shutdown
cross-connect 1 t1 1/1 1 ppp 1
cross-connect 2 t1 1/1 1 ppp 1
ip route X.X.X.X 255.255.255.0 ppp 1
Router B:
====================================
!
interface t1 1/1
clock source line
tdm-group 1 timeslots 1-24 speed 64
no shutdown
!
interface t1 1/2
clock source line
tdm-group 1 timeslots 1-24 speed 64
no shutdown
!
interface ppp 1
ip address 172.16.1.6 255.255.255.252
ppp multilink
no shutdown
cross-connect 1 t1 1/1 1 ppp 1
cross-connect 2 t1 1/1 1 ppp 1
ip route X.X.X.X 255.255.255.0 ppp 1
