Connecting a Lexicon PCM-91 to a 2011 Macbook Pro SPDIF

Can I use an RCA type SPDIF coax cable that can bee modified to a 3.5mm jack on the other end so I can digitally send the audio into the Macbook Pro (using my software for capture)? When I go into the AudioMidi preferences it defaults (with no option to change via a drop down box or other) to LINE IN (analog). Searching the forums has been confusing to me. I thought I read that the default LINE IN will change on it's own to DIGITAL IN when it receives a SPDIF signal. I don't have the cable or adaptors to do this yes, but I don't want to use another piece of hardware in the chain to do this. I have an Apogee Mini Me, but I don't believe that has a digital in, just analog in. I record on location with a Nagra, digital into my Lexicon PCM91 and then go into my audio card in my PC tower - but now I have a Macbook Pro (2011 17") and want to use it and sell my tower (even though it's an awesome build).

Thank you for helping me.