I ran into a problem with DMVPN and what looks like a conflict with PPTP/NAT.
There are some posts here recommending 12.3(9) - is there a 12.4 mainline release or CSC for the issue that I can find working releases?
Hub is 12.4(25c) and spokes are 12(4)15-T3
ipsec dmvpn tunnels were mysteriously dropping, while straight ipip point to point tunnels had no issue. crypto was working etc. but showing no encaps on the hub and no nhrp being resolved.
clear ip nhrp seemed to fix it once, but then on recurrence it didn't
Then I noticed gre translations in nat - did clear ip nat translation * and the DMVPN tunnel came back up.
- already using ipsec transport mode
ip nat inside source list 2 interface FastEthernet0/0 overload