diff --git a/src/internet/model/ipv4-end-point-demux.cc b/src/internet/model/ipv4-end-point-demux.cc
index 9bfd2f712..7c3cde2e7 100644
--- a/src/internet/model/ipv4-end-point-demux.cc
+++ b/src/internet/model/ipv4-end-point-demux.cc
@@ -27,7 +27,7 @@ namespace ns3 {
 NS_LOG_COMPONENT_DEFINE ("Ipv4EndPointDemux");
 
 Ipv4EndPointDemux::Ipv4EndPointDemux ()
-  : m_ephemeral (49152)
+  : m_ephemeral (49152), m_portLast (65535), m_portFirst (49152)
 {
   NS_LOG_FUNCTION_NOARGS ();
 }
diff --git a/src/internet/model/ipv4-end-point-demux.h b/src/internet/model/ipv4-end-point-demux.h
index a8d3a2d28..f76dff7f2 100644
--- a/src/internet/model/ipv4-end-point-demux.h
+++ b/src/internet/model/ipv4-end-point-demux.h
@@ -77,6 +77,8 @@ private:
   uint16_t AllocateEphemeralPort (void);
 
   uint16_t m_ephemeral;
+  uint16_t m_portLast;
+  uint16_t m_portFirst;
   EndPoints m_endPoints;
 };
 
diff --git a/src/internet/model/tcp-socket-base.cc b/src/internet/model/tcp-socket-base.cc
index 415a5368c..3f445dd3b 100644
--- a/src/internet/model/tcp-socket-base.cc
+++ b/src/internet/model/tcp-socket-base.cc
@@ -219,6 +219,11 @@ TcpSocketBase::Bind (void)
 {
   NS_LOG_FUNCTION_NOARGS ();
   m_endPoint = m_tcp->Allocate ();
+  if (0 == m_endPoint)
+    {
+      m_errno = ERROR_ADDRNOTAVAIL;
+      return -1;
+    }
   return SetupCallback ();
 }
 
@@ -238,6 +243,11 @@ TcpSocketBase::Bind (const Address &address)
   if (ipv4 == Ipv4Address::GetAny () && port == 0)
     {
       m_endPoint = m_tcp->Allocate ();
+      if (0 == m_endPoint)
+        {
+	  m_errno = ERROR_ADDRNOTAVAIL;
+          return -1;
+	}
     }
   else if (ipv4 == Ipv4Address::GetAny () && port != 0)
     {
@@ -251,6 +261,11 @@ TcpSocketBase::Bind (const Address &address)
   else if (ipv4 != Ipv4Address::GetAny () && port == 0)
     {
       m_endPoint = m_tcp->Allocate (ipv4);
+      if (0 == m_endPoint)
+        {
+	  m_errno = ERROR_ADDRNOTAVAIL;
+	  return -1;
+        }
     }
   else if (ipv4 != Ipv4Address::GetAny () && port != 0)
     {