I asked Mr. Niazi in Cisco this question again and received the following answer:
Here are the recommended versions now:
OS 12.4 Mainline: 12.4(3c), 12.4(5a), 12.4(7)*
IOS 12.4 T-train: 12.4(2)T4, 12.4(4)T
In general we run 12.3 or 12.4 Mainline on DMVPN hubs and 12.3T or 12.4T on DMVPN spokes, but this is not a strict rule at all.
* 12.4(7) is particularly good on the DMVPN hub routers when using EIGRP as the routing protocol, a number of EIGRP fixes/features were added that makes EIGRP more stable on DMVPN networks.
The usual disclaimer goes with the recommendation: the images have proven to be stable in our internal test and beta networks as well as most of the customer networks. Since every customer environemnt is unique, you might (a remote possibility) find some corner-case type issues in your network.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...