I would like to know if FRF.16 across 2xT1 will work on a Cisco 2621 equipped with a WIC-2T1. I have heard a WIC-2T1 version 2 is required. But then I got a contradictory statement, saying FRF.16 will also work using a WIC-2T1 v1 as long as IOS 12.2(15)T9 minimum is used.
I would hate to have to use a WIC-2T1 v2 because I will have to replace the router, a 2621 (non-XM) will not accept v2 WIC.