diff --git a/src/common/cfgfiles.c b/src/common/cfgfiles.c
index c8fcf760..89d65ed6 100644
--- a/src/common/cfgfiles.c
+++ b/src/common/cfgfiles.c
@@ -390,6 +390,9 @@ const struct prefs vars[] =
 	{"dcc_permissions", P_OFFINT (hex_dcc_permissions), TYPE_INT},
 	{"dcc_port_first", P_OFFINT (hex_dcc_port_first), TYPE_INT},
 	{"dcc_port_last", P_OFFINT (hex_dcc_port_last), TYPE_INT},
+	{"dcc_nat_lease", P_OFFINT (hex_dcc_nat_lease), TYPE_INT},
+	{"dcc_nat_map", P_OFFINT (hex_dcc_nat_map), TYPE_BOOL},
+	{"dcc_passive_prefer", P_OFFINT (hex_dcc_passive_prefer), TYPE_BOOL},
 	{"dcc_remove", P_OFFINT (hex_dcc_remove), TYPE_BOOL},
 	{"dcc_save_nick", P_OFFINT (hex_dcc_save_nick), TYPE_BOOL},
 	{"dcc_send_fillspaces", P_OFFINT (hex_dcc_send_fillspaces), TYPE_BOOL},
@@ -762,6 +765,7 @@ load_default_config(void)
 	prefs.hex_away_show_once = 1;
 	prefs.hex_away_track = 1;
 	prefs.hex_dcc_auto_resume = 1;
+	prefs.hex_dcc_passive_prefer = 1;
 #ifndef WIN32
 	prefs.hex_dcc_fast_send = 1;
 #endif
@@ -835,6 +839,7 @@ load_default_config(void)
 	prefs.hex_dcc_permissions = 0600;
 	prefs.hex_dcc_stall_timeout = 60;
 	prefs.hex_dcc_timeout = 180;
+	prefs.hex_dcc_nat_lease = 1800;
 	prefs.hex_flood_ctcp_num = 5;
 	prefs.hex_flood_ctcp_time = 30;
 	prefs.hex_flood_msg_num = 5;
diff --git a/src/common/dcc.c b/src/common/dcc.c
index a8fb68fa..8d5b7c9a 100644
--- a/src/common/dcc.c
+++ b/src/common/dcc.c
@@ -87,6 +87,41 @@ static gboolean dcc_read (GIOChannel *, GIOCondition, struct DCC *);
 static gboolean dcc_read_ack (GIOChannel *source, GIOCondition condition, struct DCC *dcc);
 static int dcc_check_timeouts (void);
 
+
+static int
+nat_map_run (int add, int port, int proto, int lease)
+{
+	char cmd[512];
+	int status = 0;
+		if (add)
+		g_snprintf (cmd, sizeof (cmd), "upnpc -a 127.0.0.1 %d %d TCP %d >/dev/null 2>&1", port, port, lease);
+	else
+		g_snprintf (cmd, sizeof (cmd), "upnpc -d %d TCP >/dev/null 2>&1", port);
+	if (!g_spawn_command_line_sync (cmd, NULL, NULL, &status, NULL))
+		return FALSE;
+	return status == 0;
+}
+
+static void
+dcc_nat_unmap (struct DCC *dcc)
+{
+	if (!dcc->map_port)
+		return;
+	nat_map_run (0, dcc->map_port, dcc->type, 0);
+	dcc->map_port = 0;
+	dcc->map_next_refresh = 0;
+}
+
+static void
+dcc_nat_refresh (struct DCC *dcc)
+{
+	if (!dcc->map_port || prefs.hex_dcc_nat_lease <= 0)
+		return;
+	if (time (0) < dcc->map_next_refresh)
+		return;
+	if (nat_map_run (1, dcc->map_port, dcc->type, prefs.hex_dcc_nat_lease))
+		dcc->map_next_refresh = time (0) + prefs.hex_dcc_nat_lease / 2;
+}
 static int new_id(void)
 {
 	static int id = 0;
@@ -254,7 +289,8 @@ dcc_check_timeouts (void)
 		switch (dcc->dccstat)
 		{
 		case STAT_ACTIVE:
-			dcc_calc_cps (dcc);
+				dcc_calc_cps (dcc);
+			dcc_nat_refresh (dcc);
 			fe_dcc_update (dcc);
 
 			if (dcc->type == TYPE_SEND || dcc->type == TYPE_RECV)
@@ -390,6 +426,7 @@ dcc_close (struct DCC *dcc, enum dcc_state dccstat, int destroy)
 	}
 
 	dcc_remove_from_sum (dcc);
+	dcc_nat_unmap (dcc);
 
 	if (dcc->fp != -1)
 	{
@@ -1698,6 +1735,11 @@ dcc_listen_init (struct DCC *dcc, session *sess)
 	getsockname (dcc->sok, (struct sockaddr *) &SAddr, &len);
 
 	dcc->port = ntohs (SAddr.sin_port);
+	if (prefs.hex_dcc_nat_map && nat_map_run (1, dcc->port, dcc->type, prefs.hex_dcc_nat_lease))
+	{
+		dcc->map_port = dcc->port;
+		dcc->map_next_refresh = time (0) + prefs.hex_dcc_nat_lease / 2;
+	}
 
 	dcc->addr = dcc_get_my_address (sess);
 
@@ -1846,8 +1888,19 @@ dcc_send (struct session *sess, char *to, char *filename, gint64 maxcps, int pas
 		return;
 	}
 
-	if (passive || dcc_listen_init (dcc, sess))
+	if ((passive || prefs.hex_dcc_passive_prefer) || dcc_listen_init (dcc, sess))
 	{
+		if (passive || prefs.hex_dcc_passive_prefer)
+		{
+			guint32 offer_addr = dcc_get_my_address (sess);
+			struct sockaddr_in saddr;
+			socklen_t slen = sizeof (saddr);
+			memset (&saddr, 0, sizeof (saddr));
+			getsockname (dcc->serv->sok, (struct sockaddr *) &saddr, &slen);
+			if (offer_addr == 0)
+				offer_addr = prefs.local_ip != 0xffffffff ? prefs.local_ip : saddr.sin_addr.s_addr;
+			dcc->addr = ntohl (offer_addr);
+		}
 		char havespaces = 0;
 		while (*filename)
 		{
@@ -1868,13 +1921,13 @@ dcc_send (struct session *sess, char *to, char *filename, gint64 maxcps, int pas
 		} else
 			fe_dcc_add (dcc);
 
-		if (passive)
+			if (passive || prefs.hex_dcc_passive_prefer)
 		{
 			dcc->pasvid = new_id();
 			g_snprintf (outbuf, sizeof (outbuf), (havespaces) ?
-					"DCC SEND \"%s\" 199 0 %" G_GUINT64_FORMAT " %d" :
-					"DCC SEND %s 199 0 %" G_GUINT64_FORMAT " %d",
-					file_part (dcc->file),
+					"DCC SEND \"%s\" %u 0 %" G_GUINT64_FORMAT " %d" :
+					"DCC SEND %s %u 0 %" G_GUINT64_FORMAT " %d",
+					file_part (dcc->file), dcc->addr,
 					dcc->size, dcc->pasvid);
 		}
 		else
@@ -2292,8 +2345,19 @@ dcc_chat (struct session *sess, char *nick, int passive)
 	dcc->dccstat = STAT_QUEUED;
 	dcc->type = TYPE_CHATSEND;
 	dcc->nick = g_strdup (nick);
-	if (passive || dcc_listen_init (dcc, sess))
+	if ((passive || prefs.hex_dcc_passive_prefer) || dcc_listen_init (dcc, sess))
 	{
+		if (passive || prefs.hex_dcc_passive_prefer)
+		{
+			guint32 offer_addr = dcc_get_my_address (sess);
+			struct sockaddr_in saddr;
+			socklen_t slen = sizeof (saddr);
+			memset (&saddr, 0, sizeof (saddr));
+			getsockname (dcc->serv->sok, (struct sockaddr *) &saddr, &slen);
+			if (offer_addr == 0)
+				offer_addr = prefs.local_ip != 0xffffffff ? prefs.local_ip : saddr.sin_addr.s_addr;
+			dcc->addr = ntohl (offer_addr);
+		}
 		if (prefs.hex_gui_autoopen_chat)
 		{
 			if (fe_dcc_open_chat_win (TRUE))	/* already open? add only */
@@ -2301,11 +2365,11 @@ dcc_chat (struct session *sess, char *nick, int passive)
 		} else
 			fe_dcc_add (dcc);
 
-		if (passive)
+		if (passive || prefs.hex_dcc_passive_prefer)
 		{
 			dcc->pasvid = new_id ();
-			g_snprintf (outbuf, sizeof (outbuf), "DCC CHAT chat 199 %d %d",
-						 dcc->port, dcc->pasvid);
+			g_snprintf (outbuf, sizeof (outbuf), "DCC CHAT chat %u 0 %d",
+						 dcc->addr, dcc->pasvid);
 		} else
 		{
 			g_snprintf (outbuf, sizeof (outbuf), "DCC CHAT chat %u %d",
diff --git a/src/common/dcc.h b/src/common/dcc.h
index c28f04d3..d696cde7 100644
--- a/src/common/dcc.h
+++ b/src/common/dcc.h
@@ -55,6 +55,9 @@ struct DCC
 	int wiotag;						/* writing/sending io tag */
 	int port;
 	int pasvid;						/* mIRC's passive DCC id */
+	int map_port;
+	int map_proto;
+	int map_next_refresh;
 	gint64 cps;
 	int resume_error;
 	int resume_errno;
diff --git a/src/common/zoitechat.h b/src/common/zoitechat.h
index 6f8591c3..3811d7f7 100644
--- a/src/common/zoitechat.h
+++ b/src/common/zoitechat.h
@@ -117,6 +117,8 @@ struct zoitechatprefs
 	unsigned int hex_dcc_remove;
 	unsigned int hex_dcc_save_nick;
 	unsigned int hex_dcc_send_fillspaces;
+	unsigned int hex_dcc_passive_prefer;
+	unsigned int hex_dcc_nat_map;
 	unsigned int hex_gui_autoopen_chat;
 	unsigned int hex_gui_autoopen_dialog;
 	unsigned int hex_gui_autoopen_recv;
@@ -241,6 +243,7 @@ struct zoitechatprefs
 	int hex_dcc_permissions;
 	int hex_dcc_port_first;
 	int hex_dcc_port_last;
+	int hex_dcc_nat_lease;
 	int hex_dcc_stall_timeout;
 	int hex_dcc_timeout;
 	int hex_flood_ctcp_num;				/* flood */
diff --git a/src/fe-gtk/setup.c b/src/fe-gtk/setup.c
index d2dc0882..16221b7b 100644
--- a/src/fe-gtk/setup.c
+++ b/src/fe-gtk/setup.c
@@ -650,6 +650,9 @@ static const setting network_settings[] =
         {ST_NUMBER,     N_("First DCC listen port:"), P_OFFINTNL(hex_dcc_port_first), 0, 0, 65535},
         {ST_NUMBER,     N_("Last DCC listen port:"), P_OFFINTNL(hex_dcc_port_last), 0, 
                 (const char **)N_("!Leave ports at zero for full range."), 65535},
+        {ST_TOGGLE, N_("Prefer passive DCC"), P_OFFINTNL(hex_dcc_passive_prefer), 0, 0, 0},
+        {ST_TOGGLE, N_("Try UPnP/NAT-PMP/PCP mapping"), P_OFFINTNL(hex_dcc_nat_map), 0, 0, 0},
+        {ST_NUMBER, N_("NAT mapping lease (sec):"), P_OFFINTNL(hex_dcc_nat_lease), 0, 0, 86400},
 
         {ST_HEADER,     N_("Proxy Server"), 0, 0, 0, 0},
         {ST_ENTRY,      N_("Hostname:"), P_OFFSETNL(hex_net_proxy_host), 0, 0, sizeof prefs.hex_net_proxy_host},