diff --git a/src/api/api_lib.c b/src/api/api_lib.c
index b4fc403d..9be38b71 100644
--- a/src/api/api_lib.c
+++ b/src/api/api_lib.c
@@ -231,6 +231,14 @@ netconn_getaddr(struct netconn *conn, ip_addr_t *addr, u16_t *port, u8_t local)
   err = netconn_apimsg(lwip_netconn_do_getaddr, &msg);
 #endif /* LWIP_MPU_COMPATIBLE */
   API_MSG_VAR_FREE(msg);
+    
+#if LWIP_IPV4 && LWIP_IPV6
+  /* Dual-stack: Map IPv4 addresses to IPv6 mapped IPv4 */
+  if (NETCONNTYPE_ISIPV6(netconn_type(conn)) && IP_IS_V4(addr)) {
+    ip4_2_ipv6_mapped_ipv4(ip_2_ip6(addr), ip_2_ip4(addr));
+    IP_SET_TYPE(addr, IPADDR_TYPE_V6);
+  }
+#endif /* LWIP_IPV4 && LWIP_IPV6 */
 
   return err;
 }
@@ -250,6 +258,7 @@ err_t
 netconn_bind(struct netconn *conn, const ip_addr_t *addr, u16_t port)
 {
   API_MSG_VAR_DECLARE(msg);
+  ip_addr_t ipaddr;
   err_t err;
   
   LWIP_ERROR("netconn_bind: invalid conn", (conn != NULL), return ERR_ARG;);
@@ -258,10 +267,28 @@ netconn_bind(struct netconn *conn, const ip_addr_t *addr, u16_t port)
   if (addr == NULL) {
     addr = IP4_ADDR_ANY;
   }
+  
+  ip_addr_copy(ipaddr, *addr);
+
+  #if LWIP_IPV4 && LWIP_IPV6
+  /* "Socket API like" dual-stack support: If IP to bind to is IP6_ADDR_ANY,
+   * and NETCONN_FLAG_IPV6_V6ONLY is 0, use IP_ANY_TYPE to bind
+   */
+  if ((netconn_get_ipv6only(conn) == 0) &&
+      ip_addr_cmp(&ipaddr, IP6_ADDR_ANY)) {
+    ip_addr_copy(ipaddr, *IP_ANY_TYPE);
+  }
+
+  /* Dual-stack: Unmap IPv6 mapped IPv4 addresses */
+  if (IP_IS_V6_VAL(ipaddr) && ip6_addr_isipv6mappedipv4(ip_2_ip6(&ipaddr))) {
+    unmap_ipv6_mapped_ipv4(ip_2_ip4(&ipaddr), ip_2_ip6(&ipaddr));
+    IP_SET_TYPE_VAL(ipaddr, IPADDR_TYPE_V4);
+  }
+#endif /* LWIP_IPV4 && LWIP_IPV6 */
 
   API_MSG_VAR_ALLOC(msg);
   API_MSG_VAR_REF(msg).conn = conn;
-  API_MSG_VAR_REF(msg).msg.bc.ipaddr = API_MSG_VAR_REF(addr);
+  API_MSG_VAR_REF(msg).msg.bc.ipaddr = API_MSG_VAR_REF(&ipaddr);
   API_MSG_VAR_REF(msg).msg.bc.port = port;
   err = netconn_apimsg(lwip_netconn_do_bind, &API_MSG_VAR_REF(msg));
   API_MSG_VAR_FREE(msg);
@@ -282,6 +309,7 @@ err_t
 netconn_connect(struct netconn *conn, const ip_addr_t *addr, u16_t port)
 {
   API_MSG_VAR_DECLARE(msg);
+  ip_addr_t ipaddr;
   err_t err;
 
   LWIP_ERROR("netconn_connect: invalid conn", (conn != NULL), return ERR_ARG;);
@@ -291,9 +319,27 @@ netconn_connect(struct netconn *conn, const ip_addr_t *addr, u16_t port)
     addr = IP4_ADDR_ANY;
   }
 
+  ip_addr_copy(ipaddr, *addr);
+
+  #if LWIP_IPV4 && LWIP_IPV6
+  /* "Socket API like" dual-stack support: If IP to bind to is IP6_ADDR_ANY,
+   * and NETCONN_FLAG_IPV6_V6ONLY is 0, use IP_ANY_TYPE to bind
+   */
+  if ((netconn_get_ipv6only(conn) == 0) &&
+      ip_addr_cmp(&ipaddr, IP6_ADDR_ANY)) {
+    ip_addr_copy(ipaddr, *IP_ANY_TYPE);
+  }
+
+  /* Dual-stack: Unmap IPv6 mapped IPv4 addresses */
+  if (IP_IS_V6_VAL(ipaddr) && ip6_addr_isipv6mappedipv4(ip_2_ip6(&ipaddr))) {
+    unmap_ipv6_mapped_ipv4(ip_2_ip4(&ipaddr), ip_2_ip6(&ipaddr));
+    IP_SET_TYPE_VAL(ipaddr, IPADDR_TYPE_V4);
+  }
+#endif /* LWIP_IPV4 && LWIP_IPV6 */
+
   API_MSG_VAR_ALLOC(msg);
   API_MSG_VAR_REF(msg).conn = conn;
-  API_MSG_VAR_REF(msg).msg.bc.ipaddr = API_MSG_VAR_REF(addr);
+  API_MSG_VAR_REF(msg).msg.bc.ipaddr = API_MSG_VAR_REF(&ipaddr);
   API_MSG_VAR_REF(msg).msg.bc.port = port;
   err = netconn_apimsg(lwip_netconn_do_connect, &API_MSG_VAR_REF(msg));
   API_MSG_VAR_FREE(msg);
@@ -561,8 +607,18 @@ netconn_recv_data(struct netconn *conn, void **new_buf)
 #endif /* LWIP_TCP && (LWIP_UDP || LWIP_RAW) */
 #if (LWIP_UDP || LWIP_RAW)
   {
+    struct netbuf* nbuf = (struct netbuf*)buf;
+    
     LWIP_ASSERT("buf != NULL", buf != NULL);
-    len = netbuf_len((struct netbuf *)buf);
+    len = netbuf_len(nbuf);
+
+#if LWIP_IPV4 && LWIP_IPV6
+    /* Dual-stack: Map IPv4 addresses to IPv6 mapped IPv4 */
+    if (NETCONNTYPE_ISIPV6(netconn_type(conn)) && IP_IS_V4_VAL(nbuf->addr)) {
+      ip4_2_ipv6_mapped_ipv4(ip_2_ip6(&nbuf->addr), ip_2_ip4(&nbuf->addr));
+      IP_SET_TYPE_VAL(nbuf->addr, IPADDR_TYPE_V6);
+    }
+#endif /* LWIP_IPV4 && LWIP_IPV6 */
   }
 #endif /* (LWIP_UDP || LWIP_RAW) */
 
@@ -697,6 +753,15 @@ netconn_send(struct netconn *conn, struct netbuf *buf)
   LWIP_ERROR("netconn_send: invalid conn",  (conn != NULL), return ERR_ARG;);
 
   LWIP_DEBUGF(API_LIB_DEBUG, ("netconn_send: sending %"U16_F" bytes\n", buf->p->tot_len));
+        
+#if LWIP_IPV4 && LWIP_IPV6
+  /* Dual-stack: Unmap IPv6 mapped IPv4 addresses */
+  if (IP_IS_V6_VAL(buf->addr) && ip6_addr_isipv6mappedipv4(ip_2_ip6(&buf->addr))) {
+    unmap_ipv6_mapped_ipv4(ip_2_ip4(&buf->addr), ip_2_ip6(&buf->addr));
+    IP_SET_TYPE_VAL(buf->addr, IPADDR_TYPE_V4);
+  }
+#endif /* LWIP_IPV4 && LWIP_IPV6 */
+
   API_MSG_VAR_ALLOC(msg);
   API_MSG_VAR_REF(msg).conn = conn;
   API_MSG_VAR_REF(msg).msg.b = buf;
diff --git a/src/api/api_msg.c b/src/api/api_msg.c
index 2b76f077..e19a6a0c 100644
--- a/src/api/api_msg.c
+++ b/src/api/api_msg.c
@@ -545,13 +545,18 @@ accept_function(void *arg, struct tcp_pcb *newpcb, err_t err)
 static void
 pcb_new(struct api_msg *msg)
 {
-  LWIP_ASSERT("pcb_new: pcb already allocated", msg->conn->pcb.tcp == NULL);
+  enum lwip_ip_addr_type iptype;
 
+  LWIP_ASSERT("pcb_new: pcb already allocated", msg->conn->pcb.tcp == NULL);
+ 
+  /* IPv6: Dual-stack by default, unless netconn_set_ipv6only() is called */
+  iptype = NETCONNTYPE_ISIPV6(netconn_type(msg->conn))? IPADDR_TYPE_ANY : IPADDR_TYPE_V4;
+  
   /* Allocate a PCB for this connection */
   switch(NETCONNTYPE_GROUP(msg->conn->type)) {
 #if LWIP_RAW
   case NETCONN_RAW:
-    msg->conn->pcb.raw = raw_new(msg->msg.n.proto);
+    msg->conn->pcb.raw = raw_new_ip_type(iptype, msg->msg.n.proto);
     if (msg->conn->pcb.raw != NULL) {
       raw_recv(msg->conn->pcb.raw, recv_raw, msg->conn);
     }
@@ -559,7 +564,7 @@ pcb_new(struct api_msg *msg)
 #endif /* LWIP_RAW */
 #if LWIP_UDP
   case NETCONN_UDP:
-    msg->conn->pcb.udp = udp_new();
+    msg->conn->pcb.udp = udp_new_ip_type(iptype);
     if (msg->conn->pcb.udp != NULL) {
 #if LWIP_UDPLITE
       if (NETCONNTYPE_ISUDPLITE(msg->conn->type)) {
@@ -575,7 +580,7 @@ pcb_new(struct api_msg *msg)
 #endif /* LWIP_UDP */
 #if LWIP_TCP
   case NETCONN_TCP:
-    msg->conn->pcb.tcp = tcp_new();
+    msg->conn->pcb.tcp = tcp_new_ip_type(iptype);
     if (msg->conn->pcb.tcp != NULL) {
       setup_tcp(msg->conn);
     }
@@ -589,15 +594,6 @@ pcb_new(struct api_msg *msg)
   if (msg->conn->pcb.ip == NULL) {
     msg->err = ERR_MEM;
   }
-#if LWIP_IPV4 && LWIP_IPV6
-  else {
-    if (NETCONNTYPE_ISIPV6(msg->conn->type)) {
-      /* Convert IPv4 PCB manually to an IPv6 PCB */
-      IP_SET_TYPE_VAL(msg->conn->pcb.ip->local_ip,  IPADDR_TYPE_V6);
-      IP_SET_TYPE_VAL(msg->conn->pcb.ip->remote_ip, IPADDR_TYPE_V6);
-    }
-  }
-#endif /* LWIP_IPV4 && LWIP_IPV6 */
 }
 
 /**
@@ -1114,37 +1110,20 @@ lwip_netconn_do_bind(void *m)
   } else {
     msg->err = ERR_VAL;
     if (msg->conn->pcb.tcp != NULL) {
-      const ip_addr_t *ipaddr = API_EXPR_REF(msg->msg.bc.ipaddr);
-
-#if LWIP_IPV4 && LWIP_IPV6
-      /* "Socket API like" dual-stack support: If IP to bind to is IP6_ADDR_ANY,
-       * and NETCONN_FLAG_IPV6_V6ONLY is NOT set, use IP_ANY_TYPE to bind
-       */
-      if (ip_addr_cmp(ipaddr, IP6_ADDR_ANY) &&
-          (netconn_get_ipv6only(msg->conn) == 0)) {
-        /* change PCB type to IPADDR_TYPE_ANY */
-        IP_SET_TYPE_VAL(msg->conn->pcb.ip->local_ip,  IPADDR_TYPE_ANY);
-        IP_SET_TYPE_VAL(msg->conn->pcb.ip->remote_ip, IPADDR_TYPE_ANY);
-        
-        /* bind to IPADDR_TYPE_ANY */
-        ipaddr = IP_ANY_TYPE;
-      }
-#endif /* LWIP_IPV4 && LWIP_IPV6 */
-
       switch (NETCONNTYPE_GROUP(msg->conn->type)) {
 #if LWIP_RAW
       case NETCONN_RAW:
-        msg->err = raw_bind(msg->conn->pcb.raw, ipaddr);
+        msg->err = raw_bind(msg->conn->pcb.raw, API_EXPR_REF(msg->msg.bc.ipaddr));
         break;
 #endif /* LWIP_RAW */
 #if LWIP_UDP
       case NETCONN_UDP:
-        msg->err = udp_bind(msg->conn->pcb.udp, ipaddr, msg->msg.bc.port);
+        msg->err = udp_bind(msg->conn->pcb.udp, API_EXPR_REF(msg->msg.bc.ipaddr), msg->msg.bc.port);
         break;
 #endif /* LWIP_UDP */
 #if LWIP_TCP
       case NETCONN_TCP:
-        msg->err = tcp_bind(msg->conn->pcb.tcp, ipaddr, msg->msg.bc.port);
+        msg->err = tcp_bind(msg->conn->pcb.tcp, API_EXPR_REF(msg->msg.bc.ipaddr), msg->msg.bc.port);
         break;
 #endif /* LWIP_TCP */
       default:
@@ -1398,15 +1377,6 @@ lwip_netconn_do_send(void *m)
   } else {
     msg->err = ERR_CONN;
     if (msg->conn->pcb.tcp != NULL) {
-      
-#if LWIP_IPV4 && LWIP_IPV6
-    /* Dual-stack: Unmap IPv6 mapped IPv4 addresses */
-    if (NETCONNTYPE_ISIPV6(netconn_type(msg->conn)) && ip6_addr_isipv6mappedipv4(ip_2_ip6(&msg->msg.b->addr))) {
-      unmap_ipv6_mapped_ipv4(ip_2_ip4(&msg->msg.b->addr), ip_2_ip6(&msg->msg.b->addr));
-      IP_SET_TYPE(&msg->msg.b->addr, IPADDR_TYPE_V4);
-    }
-#endif /* LWIP_IPV4 && LWIP_IPV6 */
-      
       switch (NETCONNTYPE_GROUP(msg->conn->type)) {
 #if LWIP_RAW
       case NETCONN_RAW:
@@ -1720,14 +1690,6 @@ lwip_netconn_do_getaddr(void *m)
       ip_addr_copy(API_EXPR_DEREF(msg->msg.ad.ipaddr),
         msg->conn->pcb.ip->remote_ip);
     }
-    
-#if LWIP_IPV4 && LWIP_IPV6
-    /* Dual-stack: Map IPv4 addresses to IPv6 */
-    if (NETCONNTYPE_ISIPV6(netconn_type(msg->conn)) && IP_IS_V4_VAL(API_EXPR_DEREF(msg->msg.ad.ipaddr))) {
-      ip4_2_ipv6_mapped_ipv4(ip_2_ip6(&API_EXPR_DEREF(msg->msg.ad.ipaddr)), ip_2_ip4(&API_EXPR_DEREF(msg->msg.ad.ipaddr)));
-      IP_SET_TYPE_VAL(API_EXPR_DEREF(msg->msg.ad.ipaddr), IPADDR_TYPE_V6);
-    }
-#endif /* LWIP_IPV4 && LWIP_IPV6 */
 
     msg->err = ERR_OK;
     switch (NETCONNTYPE_GROUP(msg->conn->type)) {
diff --git a/src/include/lwip/api.h b/src/include/lwip/api.h
index e8620dd8..d1394533 100644
--- a/src/include/lwip/api.h
+++ b/src/include/lwip/api.h
@@ -90,6 +90,7 @@ extern "C" {
 #define NETCONNTYPE_ISUDPLITE(t)     (((t)&0xF3) == NETCONN_UDPLITE)
 #define NETCONNTYPE_ISUDPNOCHKSUM(t) (((t)&0xF3) == NETCONN_UDPNOCHKSUM)
 #else /* LWIP_IPV6 */
+#define NETCONNTYPE_ISIPV6(t)        (0)
 #define NETCONNTYPE_ISUDPLITE(t)     ((t) == NETCONN_UDPLITE)
 #define NETCONNTYPE_ISUDPNOCHKSUM(t) ((t) == NETCONN_UDPNOCHKSUM)
 #endif /* LWIP_IPV6 */