DMVPN Phase 3 ip nhrp short / ip nhrp redirect missing

Question

Dear All, we are trying to setup DMVPN Phase 3 and need to enter the commands ip nhrp shortcut and ip nhrp redirect which is not possible on Cisco 1841 routers - IOS version advipservicesk9-mz.124-25f.bin
On a cisco 1812 c181x-advipservicesk9-mz.124-24.T4.bin we can enter the commands.
Out aommands 1841:
Router 1(config-if)#ip nhrp ?
  authentication  Authentication string
  holdtime        Advertised holdtime
  interest        Specify an access list
  map             Map dest IP addresses to NBMA addresses
  max-send        Rate limit NHRP traffic
  network-id      NBMA network identifier
  nhs             Specify a next hop server
  record          Allow NHRP record option
  registration    Settings for registration packets.
  responder       Responder interface
  server-only     Disable NHRP requests
  trigger-svc     Create NHRP cut-through based on traffic load
  use             Specify usage count for sending requests
Output commands 1812:
Router 2(config-if)#ip nhrp ?
  authentication  Authentication string
  cache           NHRP Cache related commands.
  group           NHRP group name
  holdtime        Advertised holdtime
  interest        Specify an access list
  map             Map dest IP addresses to NBMA addresses
  max-send        Rate limit NHRP traffic
  network-id      NBMA network identifier
  nhs             Specify a next hop server
  record          Allow NHRP record option
  redirect        Enable NHRP redirect traffic indication
  registration    Settings for registration packets.
  responder       Responder interface
  server-only     Disable NHRP requests
  shortcut        Enable shortcut switching
  trigger-svc     Create NHRP cut-through based on traffic load
  use             Specify usage count for sending requests
This is the information I found on the Cisco web page: "In Cisco IOS Software Release 12.4(6)T, DMVPN Phase 3 was introduced". Now I am wondering which software I shall use for the Cisco 1841 as we already use a higher version: advipservicesk9-mz.124-25f.bin
I appreciate your help
Thank you
Nikola

Answer 1

Nikola,
Let's start wit this:
http://en.wikipedia.org/wiki/Cisco_IOS#Versioning
Than what you need to understand is that T train is where we put all the new fearures. Mainline is one we rebuild with usuall no big changes, i.e. main focus is stability with less features.
That being said 12.4(25) might have a higher number than 12.4(24)T, but it will not contains some features.
Marcin