Index: chan_iax2.c
===================================================================
--- chan_iax2.c (Revision 186619)
+++ chan_iax2.c (Arbeitskopie)
@@ -270,6 +270,7 @@
                                                     response, so that we've achieved a three-way handshake with
                                                     them before sending voice or anything else*/
        IAX_ALLOWFWDOWNLOAD = (1 << 26),        /*!< Allow the FWDOWNL command? */
+       IAX_RTSAVE_SYSNAME =    (1 << 27),      /*!< Save Systname on Realtime Updates */
 } iax2_flags;

 static int global_rtautoclear = 120;
@@ -3140,12 +3141,19 @@
 {
        char port[10];
        char regseconds[20];
-
-       snprintf(regseconds, sizeof(regseconds), "%d", (int)regtime);
+        char *sysname = ast_config_AST_SYSTEM_NAME;
+        char *syslabel = NULL;
+
+       if (ast_strlen_zero(sysname))   /* No system name, disable this */
+                sysname = NULL;
+        else if (ast_test_flag(&globalflags, IAX_RTSAVE_SYSNAME))
+                syslabel = "regserver";
+
+       printf(regseconds, sizeof(regseconds), "%d", (int)regtime);
        snprintf(port, sizeof(port), "%d", ntohs(sin->sin_port));
-       ast_update_realtime("iaxpeers", "name", peername,
-               "ipaddr", ast_inet_ntoa(sin->sin_addr), "port", port,
-               "regseconds", regseconds, NULL);
+        ast_update_realtime("iaxpeers", "name", peername, "ipaddr", ast_inet_ntoa(sin->sin_addr),
+                "port", port, "regseconds", regseconds,
+                syslabel, sysname, NULL); /* note syslabel _can_ be NULL */
 }

 struct create_addr_info {
@@ -10287,6 +10295,8 @@
                        ast_set2_flag((&globalflags), ast_true(v->value), IAX_RTIGNOREREGEXPIRE);
                else if (!strcasecmp(v->name, "rtupdate"))
                        ast_set2_flag((&globalflags), ast_true(v->value), IAX_RTUPDATE);
+               else if (!strcasecmp(v->name, "rtsavesysname"))
+                        ast_set2_flag((&globalflags), ast_true(v->value), IAX_RTSAVE_SYSNAME);
                else if (!strcasecmp(v->name, "trunktimestamps"))
                        ast_set2_flag(&globalflags, ast_true(v->value), IAX_TRUNKTIMESTAMPS);
                else if (!strcasecmp(v->name, "rtautoclear")) {