Help in Configuring EAP-SIM

Hello, I am writing to inquire about the best way to configure freeradius for eap-sim. * I am using version 3.0.25 * I have a test sim peer and know the Ki, OP, and IMSI for it. How would I configure freeradius to use the Ki and OP when it receives a message from the test peer requesting to authenticate with EAP-SIM? I tried putting the Ki and OP in the users file but that didn't work. According to doc/modules/rlm_eap it says I need to write a separate module to generate GSM triplets given the Ki. However, in src/modules/rlm_eap/types/rlm_eap_sim/rlm_eap_sim.c:eap_sim_get_challenge it looks like there is already a module to generate GSM triplets given the Ki. How could I configure freeradius to call it? Thanks, Shane