diff --git a/CHANGELOG b/CHANGELOG
index 0704a818..1c94375d 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -186,6 +186,11 @@ HISTORY
 
   ++ Bugfixes:
 
+  2015-02-17: Simon Goldschmidt
+  * err.h, sockets.c, api_msg.c: fixed bug #38853 "connect() use a wrong errno":
+    return ERR_ALREADY/EALRADY during connect, ERR_ISCONN/EISCONN when already
+	connected
+
   2015-02-17: Simon Goldschmidt
   * tcp_impl.h, tcp_out.c, tcp.c, api_msg.c: fixed bug #37614 "Errors from
     ipX_output are not processed". Now tcp_output(_segment) checks for the return
diff --git a/src/api/api_msg.c b/src/api/api_msg.c
index 6663b8e9..26754887 100644
--- a/src/api/api_msg.c
+++ b/src/api/api_msg.c
@@ -1173,7 +1173,9 @@ lwip_netconn_do_connect(struct api_msg_msg *msg)
 #if LWIP_TCP
     case NETCONN_TCP:
       /* Prevent connect while doing any other action. */
-      if (msg->conn->state != NETCONN_NONE) {
+      if (msg->conn->state == NETCONN_CONNECT) {
+        msg->err = ERR_ALREADY;
+      } else if (msg->conn->state != NETCONN_NONE) {
         msg->err = ERR_ISCONN;
       } else {
         setup_tcp(msg->conn);
diff --git a/src/api/sockets.c b/src/api/sockets.c
index c0f4e73b..6dfe57eb 100644
--- a/src/api/sockets.c
+++ b/src/api/sockets.c
@@ -258,13 +258,14 @@ static const int err_to_errno_table[] = {
   EINVAL,        /* ERR_VAL        -6      Illegal value.           */
   EWOULDBLOCK,   /* ERR_WOULDBLOCK -7      Operation would block.   */
   EADDRINUSE,    /* ERR_USE        -8      Address in use.          */
-  EALREADY,      /* ERR_ISCONN     -9      Already connected.       */
-  ENOTCONN,      /* ERR_CONN       -10     Not connected.           */
-  ECONNABORTED,  /* ERR_ABRT       -11     Connection aborted.      */
-  ECONNRESET,    /* ERR_RST        -12     Connection reset.        */
-  ENOTCONN,      /* ERR_CLSD       -13     Connection closed.       */
-  EIO,           /* ERR_ARG        -14     Illegal argument.        */
-  -1,            /* ERR_IF         -15     Low-level netif error    */
+  EALREADY,      /* ERR_ALREADY    -9      Already connecting.      */
+  EISCONN,       /* ERR_ISCONN     -10     Conn already established.*/
+  ENOTCONN,      /* ERR_CONN       -11     Not connected.           */
+  ECONNABORTED,  /* ERR_ABRT       -12     Connection aborted.      */
+  ECONNRESET,    /* ERR_RST        -13     Connection reset.        */
+  ENOTCONN,      /* ERR_CLSD       -14     Connection closed.       */
+  EIO,           /* ERR_ARG        -15     Illegal argument.        */
+  -1,            /* ERR_IF         -16     Low-level netif error    */
 };
 
 #define ERR_TO_ERRNO_TABLE_SIZE \
diff --git a/src/include/lwip/err.h b/src/include/lwip/err.h
index a48430d2..0f0087d8 100644
--- a/src/include/lwip/err.h
+++ b/src/include/lwip/err.h
@@ -58,20 +58,21 @@ typedef s8_t err_t;
 #define ERR_VAL        -6    /* Illegal value.           */
 #define ERR_WOULDBLOCK -7    /* Operation would block.   */
 #define ERR_USE        -8    /* Address in use.          */
-#define ERR_ISCONN     -9    /* Already connected.       */
+#define ERR_ALREADY    -9    /* Already connecting.      */
+#define ERR_ISCONN     -10   /* Conn already established.*/
 
 #define ERR_IS_FATAL(e) ((e) < ERR_ISCONN)
 
-#define ERR_CONN       -10   /* Not connected.           */
+#define ERR_CONN       -11   /* Not connected.           */
 #define ERR_IS_FATAL_LISTENCONNECT(e) ((e) < ERR_CONN)
 
-#define ERR_ABRT       -11   /* Connection aborted.      */
-#define ERR_RST        -12   /* Connection reset.        */
-#define ERR_CLSD       -13   /* Connection closed.       */
+#define ERR_ABRT       -12   /* Connection aborted.      */
+#define ERR_RST        -13   /* Connection reset.        */
+#define ERR_CLSD       -14   /* Connection closed.       */
 
-#define ERR_ARG        -14   /* Illegal argument.        */
+#define ERR_ARG        -15   /* Illegal argument.        */
 
-#define ERR_IF         -15   /* Low-level netif error    */
+#define ERR_IF         -16   /* Low-level netif error    */
 
 
 #ifdef LWIP_DEBUG