Hi Roger.
I am using a totally different approach, but I think it would allow you to do what you want without needing a second IR receiver. I am using an old iPAQ 3950 with TV Remote Controller 5 from pdawin.com to emulate a Philips Pronto universal remote control. The RC is able to learn IR codes from any equipment. Furthermore, the codes to emulate MCE keyboards and RCs are available in the libraries of RemoteCentral.com.
With this solution, I haven't needed to use any replacement drivers. As an alternative to replacement drivers (which are apparently device-specific, judging from the exchange above) you may want the consider EventGhost, which allows you to remap keycodes to events. In other words, it intercepts the commands in the Windows Messaging System (after the driver). Even if my approach with the Pronot emulation doesn't appeal to you, EventGhost might enable you to get what you want using only one IR receiver.
Regards,
Roger
SCALEO E /P4 524/BB SCALEO E
3GHz Intel P4 (HT) w/3GB RAM
xpMCE 2005 RU2
Grafikkarte: NVIDIA GeForce 6600
HDD: SAMSUNG HD501LJ (500 GB)
NIC: Realtek RTL8139/810x Family Fast Ethernet NIC
TV: Hauppauge WinTV-HVR 1300 MCE (WinTV 88x)