--- mqtt/src/dl.c	2011/11/25 15:29:30	1.1.2.10
+++ mqtt/src/dl.c	2011/11/29 22:42:23	1.1.2.11
@@ -78,6 +78,11 @@ mqttLoadRTLM(sl_config *cfg, int modtype)
 			call.OpenACC = mqttOpenRTLM;
 			call.CloseACC = mqttCloseRTLM;
 			call.LoginACC = dlsym(rtlm, "mqtt_rtlm_login");
+			if (!call.LoginACC) {
+				mqttLog("Error:: incorrect module ...\n");
+				dlclose(rtlm);
+				return NULL;
+			}
 			break;
 		case 1:
 			pub_rtlm = rtlm;
@@ -89,12 +94,23 @@ mqttLoadRTLM(sl_config *cfg, int modtype)
 			call.WritePUB = dlsym(rtlm, "mqtt_rtlm_write_topic");
 			call.ReadPUB = dlsym(rtlm, "mqtt_rtlm_read_topic");
 			call.DeletePUB = dlsym(rtlm, "mqtt_rtlm_delete_topic");
+			if (!call.InitSessPUB || !call.FiniSessPUB || !call.ChkSessPUB || 
+					!call.WritePUB || !call.ReadPUB || !call.DeletePUB) {
+				mqttLog("Error:: incorrect module ...\n");
+				dlclose(rtlm);
+				return NULL;
+			}
 			break;
 		default:
 			log_rtlm = rtlm;
 			call.OpenLOG = mqttOpenRTLM;
 			call.CloseLOG = mqttCloseRTLM;
 			call.LOG = dlsym(rtlm, "mqtt_rtlm_logger");
+			if (!call.LOG) {
+				mqttLog("Error:: incorrect module ...\n");
+				dlclose(rtlm);
+				return NULL;
+			}
 			break;
 	}