diff --git a/ChangeLog b/ChangeLog
index c6022f9d4..259c727e5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,11 @@
 
 	* Source/NSTimeZone.m: Remove unnecessary check on fiel name as
 	Roland Schwingel reported that it caught legitimate files on windows.
+	* Source/NSMessagePort.m:
+	* Source/NSSocketPort.m:
+	Protect -release with lock and remove port from gloibal table within
+	protected region, to avoid possible double deallocation in a
+	multithreaded process.
 
 2006-09-09  Richard Frith-Macdonald <rfm@gnu.org>
 
diff --git a/Source/NSMessagePort.m b/Source/NSMessagePort.m
index 73205cc44..9d7a6582c 100644
--- a/Source/NSMessagePort.m
+++ b/Source/NSMessagePort.m
@@ -1574,14 +1574,14 @@ typedef	struct {
 	  unsigned	i;
 
 	  M_LOCK(messagePortLock);
+	  NSMapRemove(messagePortMap, (void*)name);
+	  M_UNLOCK(messagePortLock);
 	  if (lDesc >= 0)
 	    {
 	      (void) close(lDesc);
 	      unlink([name bytes]);
 	      lDesc = -1;
 	    }
-	  NSMapRemove(messagePortMap, (void*)name);
-	  M_UNLOCK(messagePortLock);
 
 	  if (handles != 0)
 	    {
@@ -1691,6 +1691,21 @@ typedef	struct {
     }
 }
 
+- (void) release
+{
+  M_LOCK(messagePortLock);
+  if (NSDecrementExtraRefCountWasZero(self))
+    {
+      NSMapRemove(messagePortMap, (void*)name);
+      M_UNLOCK(messagePortLock);
+      [self dealloc];
+    }
+  else
+    {
+      M_UNLOCK(messagePortLock);
+    }
+}
+
 - (void) removeHandle: (GSMessageHandle*)handle
 {
   M_LOCK(myLock);
diff --git a/Source/NSSocketPort.m b/Source/NSSocketPort.m
index 98ab968c8..428679c92 100644
--- a/Source/NSSocketPort.m
+++ b/Source/NSSocketPort.m
@@ -18,7 +18,8 @@
 
    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
-   Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111 USA.
+   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02111 USA.
    */
 
 #include "config.h"
@@ -1693,7 +1694,8 @@ static Class		tcpPortClass;
                   NSLog(@"Invalid Event - '%d'", WSAGetLastError());
                   abort();
                 }
-              rc = WSAEventSelect(port->listener, port->eventListener, FD_ACCEPT);
+              rc = WSAEventSelect(port->listener,
+		port->eventListener, FD_ACCEPT);
               NSAssert(rc == 0, @"WSAEventSelect failed!");
 #endif
 	      /*
@@ -1725,7 +1727,8 @@ static Class		tcpPortClass;
 	   * Make sure we have the map table for this port.
 	   */
 	  port->portNum = number;
-	  thePorts = (NSMapTable*)NSMapGet(tcpPortMap, (void*)(uintptr_t)number);
+	  thePorts
+	    = (NSMapTable*)NSMapGet(tcpPortMap, (void*)(uintptr_t)number);
 	  if (thePorts == 0)
 	    {
 	      /*
@@ -1734,7 +1737,8 @@ static Class		tcpPortClass;
 	       */
 	      thePorts = NSCreateMapTable(NSIntMapKeyCallBacks,
 			      NSNonOwnedPointerMapValueCallBacks, 0);
-	      NSMapInsert(tcpPortMap, (void*)(uintptr_t)number, (void*)thePorts);
+	      NSMapInsert(tcpPortMap,
+		(void*)(uintptr_t)number, (void*)thePorts);
 	    }
 	  /*
 	   * Record the port by host.
@@ -2057,19 +2061,20 @@ static Class		tcpPortClass;
 	  thePorts = NSMapGet(tcpPortMap, (void*)(uintptr_t)portNum);
 	  if (thePorts != 0)
 	    {
-	      if (listener >= 0)
-		{
-		  (void) close(listener);
-		  listener = -1;
-#if	defined(__MINGW32__)
-                  WSACloseEvent(eventListener);
-                  eventListener = WSA_INVALID_EVENT;                   
-#endif
-		}
 	      NSMapRemove(thePorts, (void*)host);
 	    }
 	  M_UNLOCK(tcpPortLock);
 
+	  if (listener >= 0)
+	    {
+	      (void) close(listener);
+	      listener = -1;
+#if	defined(__MINGW32__)
+	      WSACloseEvent(eventListener);
+	      eventListener = WSA_INVALID_EVENT;                   
+#endif
+	    }
+
 	  if (handles != 0)
 	    {
 	      handleArray = NSAllMapTableValues(handles);
@@ -2216,6 +2221,28 @@ static Class		tcpPortClass;
     }
 }
 
+- (void) release
+{
+  M_LOCK(tcpPortLock);
+  if (NSDecrementExtraRefCountWasZero(self))
+    {
+      NSMapTable	*thePorts;
+
+      thePorts = NSMapGet(tcpPortMap, (void*)(uintptr_t)portNum);
+      if (thePorts != 0)
+	{
+	  NSMapRemove(thePorts, host);
+	}
+      M_UNLOCK(tcpPortLock);
+      [self dealloc];
+    }
+  else
+    {
+      M_UNLOCK(tcpPortLock);
+    }
+}
+
+
 /*
  * This is called when a tcp/ip socket connection is broken.  We remove the
  * connection handle from this port and, if this was the last handle to a