Failed to link to module "rlm_name" : file not found

Hi, everyone: I added a new module named rlm_name to FreeRADIUS and produced makefile as rlm_example, also I add rlm_name to src/modules/stable. When I do ./configure; make; make install, all the process are sucessful. If I do not use module rlm_name, the radius sever can run normally. But when I add rlm_name in the modules {} of radiusd.conf and run ./radiusd -X, it says Failed to link to module "rlm_name" : file not found. All the .la .lo and .a files generated can be found in /usr/local/lib. I have been searching mailing list for a long time, but every method is useless to me. Any one can help me? Thank you very much!