According to my reading of hardware compatibility guides, the HWIC-1FE should work in the 28xx routers. However, I'm having a problem with it in 2811's. I've tried two different HWIC-1FE's in different slots of two different 2811 routers, and get something like this at bootup:
%GT96K_FEWAN-1-UNKNOWN_WIC: NM slot 0, wic card has an unknown id 53Asslinit fn
Am I misintepreting something here?
As i say you need a 12.4T version of software. You have a 12.4 version. The hardware support for the HWIC-IFE for the 2800's was added in the T train.