Index: channels/chan_agent.c
===================================================================
--- channels/chan_agent.c	(revision 7924)
+++ channels/chan_agent.c	(working copy)
@@ -1269,6 +1269,26 @@
 	return res;
 }
 
+/* return 0 if there are no same loginchan name */
+static int check_extension(char *chan, char *context)
+{
+	struct agent_pvt *p;
+	char loginchan[80];
+
+	if(!chan || !context)
+		return 0;
+
+	snprintf(loginchan, sizeof(loginchan), "%s@%s", chan, !ast_strlen_zero(context) ? context : "default");
+
+	p = agents;
+	while(p) {
+		if(!strcasecmp(loginchan, p->loginchan))
+			return -1;
+		p = p->next;
+	}
+	return 0;
+}
+
 /*--- agent_request: Part of the Asterisk PBX interface ---*/
 static struct ast_channel *agent_request(const char *type, int format, void *data, int *cause)
 {
@@ -1837,9 +1857,11 @@
 								res = 0;
 							} else
 								res = ast_app_getdata(chan, "agent-newlocation", tmpchan+pos, sizeof(tmpchan) - 2, 0);
-							if (ast_strlen_zero(tmpchan) || ast_exists_extension(chan, !ast_strlen_zero(context) ? context : "default", tmpchan,
-													     1, NULL))
+							if (ast_strlen_zero(tmpchan))
 								break;
+							
+							if (!check_extension(chan, context) && ast_exists_extension(chan, !ast_strlen_zero(context) ? context : "default", tmpchan, 1, NULL))
+								break;
 							if (args.extension) {
 								ast_log(LOG_WARNING, "Extension '%s' is not valid for automatic login of agent '%s'\n", args.extension, p->agent);
 								args.extension = NULL;