diff --git a/common/os_calls.c b/common/os_calls.c
index e7fc144c..6289c276 100644
--- a/common/os_calls.c
+++ b/common/os_calls.c
@@ -3823,3 +3823,132 @@ g_mirror_memcpy(void *dst, const void *src, int len)
     return 0;
 }
 
+/*****************************************************************************/
+int
+g_tcp4_socket(void)
+{
+#if defined(XRDP_ENABLE_IPV6ONLY)
+    return -1;
+#else
+    int rv;
+    int option_value;
+    socklen_t option_len;
+
+    rv = socket(AF_INET, SOCK_STREAM, 0);
+    if (rv < 0)
+    {
+        return -1;
+    }
+    option_len = sizeof(option_value);
+    if (getsockopt(rv, SOL_SOCKET, SO_REUSEADDR,
+                   (char *) &option_value, &option_len) == 0)
+    {
+        if (option_value == 0)
+        {
+            option_value = 1;
+            option_len = sizeof(option_value);
+            if (setsockopt(rv, SOL_SOCKET, SO_REUSEADDR,
+                           (char *) &option_value, option_len) < 0)
+            {
+            }
+        }
+    }
+    return rv;
+#endif
+}
+
+/*****************************************************************************/
+int
+g_tcp4_bind(int sck, const char *port, const char *address)
+{
+#if defined(XRDP_ENABLE_IPV6ONLY)
+    return -1;
+#else
+    struct sockaddr_in s;
+
+    memset(&s, 0, sizeof(s));
+    s.sin_family = AF_INET;
+    s.sin_addr.s_addr = htonl(INADDR_ANY);
+    s.sin_port = htons((uint16_t) atoi(port));
+    if (bind(sck, (struct sockaddr*) &s, sizeof(s)) == 0)
+    {
+        return 0;
+    }
+    return -1;
+#endif
+}
+
+/*****************************************************************************/
+int
+g_tcp6_socket(void)
+{
+#if defined(XRDP_ENABLE_IPV6)
+    int rv;
+    int option_value;
+    socklen_t option_len;
+
+    rv = socket(AF_INET6, SOCK_STREAM, 0);
+    if (rv < 0)
+    {
+        return -1;
+    }
+    option_len = sizeof(option_value);
+    if (getsockopt(rv, IPPROTO_IPV6, IPV6_V6ONLY,
+                   (char *) &option_value, &option_len) == 0)
+    {
+#if defined(XRDP_ENABLE_IPV6ONLY)
+        if (option_value == 0)
+        {
+            option_value = 1;
+#else
+        if (option_value != 0)
+        {
+            option_value = 0;
+#endif
+            option_len = sizeof(option_value);
+            if (setsockopt(rv, IPPROTO_IPV6, IPV6_V6ONLY,
+                           (char *) &option_value, option_len) < 0)
+            {
+            }
+        }
+    }
+    option_len = sizeof(option_value);
+    if (getsockopt(rv, SOL_SOCKET, SO_REUSEADDR,
+                   (char *) &option_value, &option_len) == 0)
+    {
+        if (option_value == 0)
+        {
+            option_value = 1;
+            option_len = sizeof(option_value);
+            if (setsockopt(rv, SOL_SOCKET, SO_REUSEADDR,
+                           (char *) &option_value, option_len) < 0)
+            {
+            }
+        }
+    }
+    return rv;
+#else
+    return -1;
+#endif
+}
+
+/*****************************************************************************/
+int
+g_tcp6_bind(int sck, const char *port, const char *address)
+{
+#if defined(XRDP_ENABLE_IPV6)
+    struct sockaddr_in6 sa;
+
+    memset(&sa, 0, sizeof(sa));
+    sa.sin6_family = AF_INET6;
+    sa.sin6_addr = in6addr_any;
+    sa.sin6_port = htons((uint16_t) atoi(port));
+    if (bind(sck, (struct sockaddr *) &sa, sizeof(sa)) == 0)
+    {
+        return 0;
+    }
+    return -1;
+#else
+    return -1;
+#endif
+}
diff --git a/common/os_calls.h b/common/os_calls.h
index e42e95bd..6cbe499a 100644
--- a/common/os_calls.h
+++ b/common/os_calls.h
@@ -183,6 +183,10 @@ void *   g_shmat(int shmid);
 int      g_shmdt(const void *shmaddr);
 int      g_gethostname(char *name, int len);
 int      g_mirror_memcpy(void *dst, const void *src, int len);
+int      g_tcp4_socket(void);
+int      g_tcp4_bind(int sck, const char *port, const char *address);
+int      g_tcp6_socket(void);
+int      g_tcp6_bind(int sck, const char *port, const char *address);
 
 /* glib-style wrappers */
 #define g_new(struct_type, n_structs) \
diff --git a/common/trans.c b/common/trans.c
index 0882d643..608b8819 100644
--- a/common/trans.c
+++ b/common/trans.c
@@ -885,7 +885,42 @@ trans_listen_address(struct trans *self, char *port, const char *address)
             }
         }
     }
-
+    else if (self->mode == TRANS_MODE_TCP4) /* tcp4 */
+    {
+        self->sck = g_tcp4_socket();
+        if (self->sck < 0)
+        {
+            return 1;
+        }
+        g_tcp_set_non_blocking(self->sck);
+        if (g_tcp4_bind(self->sck, port, address) == 0)
+        {
+            if (g_tcp_listen(self->sck) == 0)
+            {
+                self->status = TRANS_STATUS_UP; /* ok */
+                self->type1 = TRANS_TYPE_LISTENER; /* listener */
+                return 0;
+            }
+        }
+    }
+    else if (self->mode == TRANS_MODE_TCP6) /* tcp6 */
+    {
+        self->sck = g_tcp6_socket();
+        if (self->sck < 0)
+        {
+            return 1;
+        }
+        g_tcp_set_non_blocking(self->sck);
+        if (g_tcp6_bind(self->sck, port, address) == 0)
+        {
+            if (g_tcp_listen(self->sck) == 0)
+            {
+                self->status = TRANS_STATUS_UP; /* ok */
+                self->type1 = TRANS_TYPE_LISTENER; /* listener */
+                return 0;
+            }
+        }
+    }
     return 1;
 }
 
diff --git a/common/trans.h b/common/trans.h
index 30559347..1e1efd16 100644
--- a/common/trans.h
+++ b/common/trans.h
@@ -24,9 +24,11 @@
 #include "arch.h"
 #include "parse.h"
 
-#define TRANS_MODE_TCP 1
+#define TRANS_MODE_TCP 1 /* tcp6 if defined, else tcp4 */
 #define TRANS_MODE_UNIX 2
 #define TRANS_MODE_VSOCK 3
+#define TRANS_MODE_TCP4 4 /* tcp4 only */
+#define TRANS_MODE_TCP6 6 /* tcp6 only */
 
 #define TRANS_TYPE_LISTENER 1
 #define TRANS_TYPE_SERVER 2
diff --git a/xrdp/xrdp_listen.c b/xrdp/xrdp_listen.c
index b484ff09..1ce84a7d 100644
--- a/xrdp/xrdp_listen.c
+++ b/xrdp/xrdp_listen.c
@@ -470,7 +470,7 @@ xrdp_listen_pp(struct xrdp_listen *self, int *index,
             bytes = xrdp_listen_parse_integer(port, 128, str, str_end - str);
             str += bytes;
             lindex += bytes;
-            *mode = TRANS_MODE_TCP;
+            *mode = TRANS_MODE_TCP4;
             *index = lindex;
             return 0;
         }
@@ -482,7 +482,7 @@ xrdp_listen_pp(struct xrdp_listen *self, int *index,
             bytes = xrdp_listen_parse_integer(port, 128, str, str_end - str);
             str += bytes;
             lindex += bytes;
-            *mode = TRANS_MODE_TCP;
+            *mode = TRANS_MODE_TCP4;
             *index = lindex;
             return 0;
         }
@@ -496,7 +496,7 @@ xrdp_listen_pp(struct xrdp_listen *self, int *index,
             bytes = xrdp_listen_parse_integer(port, 128, str, str_end - str);
             str += bytes;
             lindex += bytes;
-            *mode = TRANS_MODE_TCP;
+            *mode = TRANS_MODE_TCP4;
             *index = lindex;
             return 0;
         }
@@ -508,7 +508,7 @@ xrdp_listen_pp(struct xrdp_listen *self, int *index,
             bytes = xrdp_listen_parse_integer(port, 128, str, str_end - str);
             str += bytes;
             lindex += bytes;
-            *mode = TRANS_MODE_TCP;
+            *mode = TRANS_MODE_TCP6;
             *index = lindex;
             return 0;
         }
@@ -520,7 +520,7 @@ xrdp_listen_pp(struct xrdp_listen *self, int *index,
             bytes = xrdp_listen_parse_integer(port, 128, str, str_end - str);
             str += bytes;
             lindex += bytes;
-            *mode = TRANS_MODE_TCP;
+            *mode = TRANS_MODE_TCP6;
             *index = lindex;
             return 0;
         }
@@ -534,7 +534,7 @@ xrdp_listen_pp(struct xrdp_listen *self, int *index,
             bytes = xrdp_listen_parse_integer(port, 128, str, str_end - str);
             str += bytes;
             lindex += bytes;
-            *mode = TRANS_MODE_TCP;
+            *mode = TRANS_MODE_TCP6;
             *index = lindex;
             return 0;
         }