How to fetch triplets from HLR?

Hi, all: Several EAP types are supported by freeradius including SIM and AKA with a patch. In case of EAP-SIM, the rlm_eap_sim module can calculate tripelets itself, and also can obtain triplets from an exist file by using rlm_sim_file module. The rlm_sim_module reads triplets from the file named simtriplets.dat. (1) I believe that triplets can also be obtains from a external palce, am I right? (2) If I want to fetch triplets from a HLR of GSM network, how could I do? Wether I need to add a module like rlm_sim_file? How to add such a module? (3) Does this module exist? Some one using EAP-AKA is also prefered! Thank you!