Index: tao/Connection_Handler.h
===================================================================
--- tao/Connection_Handler.h	(revision 85694)
+++ tao/Connection_Handler.h	(working copy)
@@ -136,6 +136,11 @@
   /// Release the OS resources related to this handler.
   virtual int release_os_resources (void);
 
+  virtual bool get_blocking_io ();
+
+  ///@return success/failure in changing blocking io mode
+  virtual bool set_blocking_io (bool block);
+
   /*
    * Hook to add public methods from concrete connection handler
    * implementation onto the base connection handler.
Index: tao/Block_Flushing_Strategy.cpp
===================================================================
--- tao/Block_Flushing_Strategy.cpp	(revision 85701)
+++ tao/Block_Flushing_Strategy.cpp	(working copy)
@@ -3,11 +3,40 @@
 #include "tao/Block_Flushing_Strategy.h"
 #include "tao/Transport.h"
 #include "tao/Queued_Message.h"
+#include "tao/Connection_Handler.h"
 
 ACE_RCSID(tao, Block_Flushing_Strategy, "$Id$")
 
 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
 
+namespace
+{
+  struct Blocking_Guard
+  {
+    explicit Blocking_Guard (TAO_Transport *t)
+      : transport_ (t)
+      , restore_nonblock_ (!t->connection_handler ()->get_blocking_io ())
+    {
+      if (this->restore_nonblock_)
+        {
+          t->connection_handler ()->set_blocking_io (true);
+        }
+    }
+
+    ~Blocking_Guard ()
+    {
+      if (this->restore_nonblock_)
+        {
+          this->transport_->connection_handler ()->set_blocking_io (false);
+        }
+    }
+
+    TAO_Transport *transport_;
+    bool restore_nonblock_;
+  };
+}
+
+
 int
 TAO_Block_Flushing_Strategy::schedule_output (TAO_Transport *)
 {
@@ -25,6 +54,7 @@
                                             TAO_Queued_Message *msg,
                                             ACE_Time_Value *max_wait_time)
 {
+  Blocking_Guard g (transport);
   while (!msg->all_data_sent ())
     {
       TAO::Transport::Drain_Constraints dc(
@@ -39,6 +69,7 @@
 TAO_Block_Flushing_Strategy::flush_transport (TAO_Transport *transport,
                                               ACE_Time_Value *max_wait_time)
 {
+  Blocking_Guard g (transport);
   while (!transport->queue_is_empty ())
     {
       TAO::Transport::Drain_Constraints dc(
Index: tao/IIOP_Connection_Handler.cpp
===================================================================
--- tao/IIOP_Connection_Handler.cpp	(revision 85694)
+++ tao/IIOP_Connection_Handler.cpp	(working copy)
@@ -58,7 +58,8 @@
 TAO_IIOP_Connection_Handler::TAO_IIOP_Connection_Handler (ACE_Thread_Manager *t)
   : TAO_IIOP_SVC_HANDLER (t, 0 , 0),
     TAO_Connection_Handler (0),
-    dscp_codepoint_ (IPDSFIELD_DSCP_DEFAULT << 2)
+    dscp_codepoint_ (IPDSFIELD_DSCP_DEFAULT << 2),
+    blocking_io_ (false)
 {
   // This constructor should *never* get called, it is just here to
   // make the compiler happy: the default implementation of the
@@ -73,7 +74,8 @@
   TAO_ORB_Core *orb_core)
   : TAO_IIOP_SVC_HANDLER (orb_core->thr_mgr (), 0, 0),
     TAO_Connection_Handler (orb_core),
-    dscp_codepoint_ (IPDSFIELD_DSCP_DEFAULT << 2)
+    dscp_codepoint_ (IPDSFIELD_DSCP_DEFAULT << 2),
+    blocking_io_ (false)
 {
   TAO_IIOP_Transport* specific_transport = 0;
   ACE_NEW (specific_transport,
@@ -258,8 +260,9 @@
         }
     }
 
-  if (this->transport ()->wait_strategy ()->non_blocking ()
-      || this->transport ()->opened_as () == TAO::TAO_SERVER_ROLE)
+  this->blocking_io_ = !this->transport ()->wait_strategy ()->non_blocking ()
+    && (this->transport ()->opened_as () != TAO::TAO_SERVER_ROLE);
+  if (!this->blocking_io_)
     {
       if (this->peer ().enable (ACE_NONBLOCK) == -1)
         return -1;
@@ -668,6 +671,37 @@
     }
 }
 
+bool TAO_IIOP_Connection_Handler::get_blocking_io ()
+{
+  return this->blocking_io_;
+}
+
+bool TAO_IIOP_Connection_Handler::set_blocking_io (bool block)
+{
+  if (block == this->blocking_io_)
+    {
+      return true;
+    }
+
+  if (block)
+    {
+      if (this->peer ().disable (ACE_NONBLOCK) == -1)
+        {
+          return false;
+        }
+    }
+  else
+    {
+      if (this->peer ().enable (ACE_NONBLOCK) == -1)
+        {
+          return false;
+        }
+    }
+  this->blocking_io_ = block;
+  return true;
+}
+
+
 //@@ CONNECTION_HANDLER_SPL_COPY_HOOK_END
 /*
  * End copy hook
Index: tao/IIOP_Connection_Handler.h
===================================================================
--- tao/IIOP_Connection_Handler.h	(revision 85694)
+++ tao/IIOP_Connection_Handler.h	(working copy)
@@ -123,6 +123,9 @@
   virtual int release_os_resources (void);
   //@}
 
+  virtual bool get_blocking_io ();
+  virtual bool set_blocking_io (bool block);
+
   // helper function used by the set_dscp_codepoint () methods to
   // set the TOS field in the IP packets.
   int set_tos (int tos);
@@ -131,6 +134,8 @@
 
   /// Stores the type of service value.
   int dscp_codepoint_;
+
+  bool blocking_io_;
 };
 
 TAO_END_VERSIONED_NAMESPACE_DECL
Index: tao/Connection_Handler.inl
===================================================================
--- tao/Connection_Handler.inl	(revision 85694)
+++ tao/Connection_Handler.inl	(working copy)
@@ -64,6 +64,24 @@
     }
 }
 
+/// Derived classes should implement these for proper support with the
+/// Blocking Flushing Strategy.
+//@{
+
+ACE_INLINE bool
+TAO_Connection_Handler::get_blocking_io ()
+{
+  return true;
+}
+
+ACE_INLINE bool
+TAO_Connection_Handler::set_blocking_io (bool)
+{
+  return true;
+}
+
+//@}
+
 //@@ CONNECTION_HANDLER_SPL_METHODS_ADD_HOOK
 
 TAO_END_VERSIONED_NAMESPACE_DECL