Yes, you can buy a digital input to stereo-RCA converter for about $70 It only works with PCM audio. I am not sure it is worth it.
http://sewelldirect.com/GefenTV-Analog-Audio-to-Digital-Converter-LeftRight-RCA-to-SPDIF-or-Toslink_specs.asp?source=froogle&utm_source=Froogle&utm_medium=cse