My exact problem is described here,<http://lists.kamailio.org/pipermail/sr-users/2013-January/076554.h… but the thread never explains how to solve the problem, *"here" = * http://lists.kamailio.org/pipermail/sr-users/2013-January/076554.html *Description of the issue: * 1. Installing Kamailio 4.1 (latest download) on a *64 bit* Linux Mint version 16 Petra 2. The system compiles cleanly. I have included MAKE and Make Install info below 3. *ims_registrar_pcscf.so will not load* 4. * ims_qos.so will not load* 5. As an FYI, cdp.so successfully loads. I mention this because cdp.so uses semaphore but does not have the sem_post problem. I compared cdp.so with ims_registrar.pcscf.soMakefiles to see if there was something obvious, but no luck. 6. As an FYI, I get the exact same error from a debian apt-get install, so using the canned Debian solution won't work for me either. 7. The config file I used is the one included with the system which I completed with some info just for testing. I have attached it purely as FYI but I don't think that is the issue. *Parts of the syslog messages relevant for issue* Jan 26 22:03:21 PC03 kamailio: ERROR: <core> [sr_module.c:599]: load_module(): ERROR: load_module: could not open module </lib64/kamailio/modules/ims_qos.so>: /lib64/kamailio/modules/*ims_qos.so:* *undefined symbol: sem_post* Jan 26 22:03:21 PC03 kamailio: ERROR: <core> [sr_module.c:599]: load_module(): ERROR: load_module: could not open module </lib64/kamailio/modules/ims_registrar_pcscf.so>: /lib64/kamailio/modules/ *ims_registrar_pcscf.so*: *undefined symbol: sem_post* *Relevent section of MAKE* CC (gcc) [M ims_qos.so] cdpeventprocessor.o CC (gcc) [M ims_qos.so] mod.o CC (gcc) [M ims_qos.so] rx_aar.o CC (gcc) [M ims_qos.so] rx_asr.o CC (gcc) [M ims_qos.so] rx_authdata.o CC (gcc) [M ims_qos.so] rx_avp.o CC (gcc) [M ims_qos.so] rx_str.o CC (gcc) [M ims_qos.so] stats.o make[2]: `libkcore.so.1.0' is up to date. make[2]: `libkamailio_ims.so.0.1' is up to date. LD (gcc) [M ims_qos.so] ims_qos.so CC (gcc) [M ims_registrar_pcscf.so] async_reginfo.o CC (gcc) [M ims_registrar_pcscf.so] reg_mod.o CC (gcc) [M ims_registrar_pcscf.so] save.o CC (gcc) [M ims_registrar_pcscf.so] service_routes.o CC (gcc) [M ims_registrar_pcscf.so] ul_callback.o make[2]: `libkcore.so.1.0' is up to date. make[2]: `libkamailio_ims.so.0.1' is up to date. LD (gcc) [M ims_registrar_pcscf.so] ims_registrar_pcscf.so CC (gcc) [M ims_registrar_scscf.so] api.o CC (gcc) [M ims_registrar_scscf.so] common.o CC (gcc) [M ims_registrar_scscf.so] config.o CC (gcc) [M ims_registrar_scscf.so] cxdx_avp.o CC (gcc) [M ims_registrar_scscf.so] cxdx_callbacks.o CC (gcc) [M ims_registrar_scscf.so] cxdx_sar.o CC (gcc) [M ims_registrar_scscf.so] lookup.o CC (gcc) [M ims_registrar_scscf.so] path.o CC (gcc) [M ims_registrar_scscf.so] registrar_notify.o CC (gcc) [M ims_registrar_scscf.so] reg_mod.o CC (gcc) [M ims_registrar_scscf.so] regpv.o CC (gcc) [M ims_registrar_scscf.so] regtime.o CC (gcc) [M ims_registrar_scscf.so] reply.o CC (gcc) [M ims_registrar_scscf.so] rerrno.o CC (gcc) [M ims_registrar_scscf.so] save.o CC (gcc) [M ims_registrar_scscf.so] server_assignment.o CC (gcc) [M ims_registrar_scscf.so] sip_msg.o CC (gcc) [M ims_registrar_scscf.so] stats.o CC (gcc) [M ims_registrar_scscf.so] userdata_parser.o CC (gcc) [M ims_registrar_scscf.so] usrloc_cb.o ---------------------------------------------------------------------------------------------------- *Make Install* LD (gcc) [M ims_icscf.so] ims_icscf.so make[2]: Nothing to be done for `install-if-newer'. make[2]: Nothing to be done for `install-if-newer'. make[2]: Nothing to be done for `install-if-newer'. touch //lib64/kamailio/modules/ims_icscf.so install -m 755 ims_icscf.so //lib64/kamailio/modules make[2]: `libkcore.so.1.0' is up to date. make[2]: `libkamailio_ims.so.0.1' is up to date. LD (gcc) [M ims_qos.so] ims_qos.so make[2]: Nothing to be done for `install-if-newer'. make[2]: Nothing to be done for `install-if-newer'. touch //lib64/kamailio/modules/ims_qos.so install -m 755 ims_qos.so //lib64/kamailio/modules make[2]: `libkcore.so.1.0' is up to date. make[2]: `libkamailio_ims.so.0.1' is up to date. LD (gcc) [M ims_registrar_pcscf.so] ims_registrar_pcscf.so make[2]: Nothing to be done for `install-if-newer'. make[2]: Nothing to be done for `install-if-newer'. touch //lib64/kamailio/modules/ims_registrar_pcscf.so install -m 755 ims_registrar_pcscf.so //lib64/kamailio/modules