3600 module NM-1FE1R2W

[whatshakin]

I have a Cisco 3600  NM-1FE1R2W module I would like to get working in my 2621 if possible.  However, all the docs I have found on this module indicate it is only compatible with the 3600 series routers.  I plugged it into the 2621 for the heck of it and it powers up OK (LED's) but the IOS does not see it.   Has anyone gotten one of these to work in a 26XX router and if so, what was the trick please?   Cheers