If I understand the situation correctly, no it's not possible. On the SL-5500 you could actually get access to the IR transmitter in a sort of "raw" mode, allowing you to actually turn it on and off manually in a way that made it behave like a TV remote. On the SL-Cxx00 hardware, even the kernel can only address it as a serial port. If I'm wrong or if the situation has changed (since 2005 or so, when I last looked at this), I would love to hear about it.
-John