diff --git a/Misc/NEWS b/Misc/NEWS
index 3c86cf23057..96256f523ea 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -149,9 +149,10 @@ Core and Builtins
 Library
 -------
 
-- Partial fix to issue #1731706: memory leak in Tkapp_Call when calling
-  from a thread different than the one that created the Tcl interpreter.
-  Patch by Robert Hancock.
+- Issue #1731706: Call Tcl_ConditionFinalize for Tcl_Conditions that will
+  not be used again (this requires Tcl/Tk 8.3.1), also fix a memory leak in
+  Tkapp_Call when calling from a thread different than the one that created
+  the Tcl interpreter. Patch by Robert Hancock.
 
 - Issue #1520877: Now distutils.sysconfig reads $AR from the 
   environment/Makefile. Patch by Douglas Greiman.
diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index 79fa6327ae3..5b1de8c7a30 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -9,9 +9,9 @@ Copyright (C) 1994 Steen Lumholt.
 
 /* TCL/TK VERSION INFO:
 
-	Only Tcl/Tk 8.2 and later are supported.  Older versions are not
-	supported.  (Use Python 2.2 if you cannot upgrade your Tcl/Tk
-	libraries.)
+	Only Tcl/Tk 8.3.1 and later are supported.  Older versions are not
+	supported. Use Python 2.6 or older if you cannot upgrade your
+	Tcl/Tk libraries.
 */
 
 /* XXX Further speed-up ideas, involving Tcl 8.0 features:
@@ -1110,7 +1110,7 @@ typedef struct Tkapp_CallEvent {
 	int flags;
 	PyObject **res;
 	PyObject **exc_type, **exc_value, **exc_tb;
-	Tcl_Condition done;
+	Tcl_Condition *done;
 } Tkapp_CallEvent;
 
 void
@@ -1261,7 +1261,7 @@ Tkapp_CallProc(Tkapp_CallEvent *e, int flags)
 done:
 	/* Wake up calling thread. */
 	Tcl_MutexLock(&call_mutex);
-	Tcl_ConditionNotify(&e->done);
+	Tcl_ConditionNotify(e->done);
 	Tcl_MutexUnlock(&call_mutex);
 	return 1;
 }
@@ -1299,6 +1299,7 @@ Tkapp_Call(PyObject *selfptr, PyObject *args)
 		/* We cannot call the command directly. Instead, we must
 		   marshal the parameters to the interpreter thread. */
 		Tkapp_CallEvent *ev;
+		Tcl_Condition cond = NULL;
 		PyObject *exc_type, *exc_value, *exc_tb;
 		if (!WaitForMainloop(self))
 			return NULL;
@@ -1310,9 +1311,9 @@ Tkapp_Call(PyObject *selfptr, PyObject *args)
 		ev->exc_type = &exc_type;
 		ev->exc_value = &exc_value;
 		ev->exc_tb = &exc_tb;
-		ev->done = (Tcl_Condition)0;
+		ev->done = &cond;
 
-		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &ev->done, &call_mutex);
+		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &cond, &call_mutex);
 
 		if (res == NULL) {
 			if (exc_type)
@@ -1320,6 +1321,7 @@ Tkapp_Call(PyObject *selfptr, PyObject *args)
 			else
 				PyErr_SetObject(Tkinter_TclError, exc_value);
 		}
+		Tcl_ConditionFinalize(&cond);
 	}
 	else 
 #endif
@@ -1505,7 +1507,7 @@ typedef struct VarEvent {
 	PyObject **res;
 	PyObject **exc_type;
 	PyObject **exc_val;
-	Tcl_Condition cond;
+	Tcl_Condition *cond;
 } VarEvent;
 
 static int
@@ -1545,7 +1547,7 @@ var_proc(VarEvent* ev, int flags)
 	ENTER_PYTHON
         var_perform(ev);
 	Tcl_MutexLock(&var_mutex);
-	Tcl_ConditionNotify(&ev->cond);
+	Tcl_ConditionNotify(ev->cond);
 	Tcl_MutexUnlock(&var_mutex);
 	LEAVE_PYTHON
 	return 1;
@@ -1560,6 +1562,7 @@ var_invoke(EventFunc func, PyObject *selfptr, PyObject *args, int flags)
 		TkappObject *self = (TkappObject*)selfptr;
 		VarEvent *ev;
 		PyObject *res, *exc_type, *exc_val;
+		Tcl_Condition cond = NULL;
 		
 		/* The current thread is not the interpreter thread.  Marshal
 		   the call to the interpreter thread, then wait for
@@ -1576,9 +1579,10 @@ var_invoke(EventFunc func, PyObject *selfptr, PyObject *args, int flags)
 		ev->res = &res;
 		ev->exc_type = &exc_type;
 		ev->exc_val = &exc_val;
-		ev->cond = NULL;
+		ev->cond = &cond;
 		ev->ev.proc = (Tcl_EventProc*)var_proc;
-		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &ev->cond, &var_mutex);
+		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &cond, &var_mutex);
+		Tcl_ConditionFinalize(&cond);
 		if (!res) {
 			PyErr_SetObject(exc_type, exc_val);
 			Py_DECREF(exc_type);
@@ -2065,7 +2069,7 @@ typedef struct CommandEvent{
 	int create;
 	int *status;
 	ClientData *data;
-	Tcl_Condition done;
+	Tcl_Condition *done;
 } CommandEvent;
 
 static int
@@ -2078,7 +2082,7 @@ Tkapp_CommandProc(CommandEvent *ev, int flags)
 	else
 		*ev->status = Tcl_DeleteCommand(ev->interp, ev->name);
 	Tcl_MutexLock(&command_mutex);
-	Tcl_ConditionNotify(&ev->done);
+	Tcl_ConditionNotify(ev->done);
 	Tcl_MutexUnlock(&command_mutex);
 	return 1;
 }
@@ -2114,6 +2118,7 @@ Tkapp_CreateCommand(PyObject *selfptr, PyObject *args)
 	data->func = func;
 	
 	if (self->threaded && self->thread_id != Tcl_GetCurrentThread()) {
+		Tcl_Condition cond = NULL;
 		CommandEvent *ev = (CommandEvent*)ckalloc(sizeof(CommandEvent));
 		ev->ev.proc = (Tcl_EventProc*)Tkapp_CommandProc;
 		ev->interp = self->interp;
@@ -2121,8 +2126,9 @@ Tkapp_CreateCommand(PyObject *selfptr, PyObject *args)
 		ev->name = cmdName;
 		ev->data = (ClientData)data;
 		ev->status = &err;
-		ev->done = NULL;
-		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &ev->done, &command_mutex);
+		ev->done = &cond;
+		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &cond, &command_mutex);
+		Tcl_ConditionFinalize(&cond);
 	}
 	else {
 		ENTER_TCL
@@ -2153,6 +2159,7 @@ Tkapp_DeleteCommand(PyObject *selfptr, PyObject *args)
 	if (!PyArg_ParseTuple(args, "s:deletecommand", &cmdName))
 		return NULL;
 	if (self->threaded && self->thread_id != Tcl_GetCurrentThread()) {
+		Tcl_Condition cond = NULL;
 		CommandEvent *ev;
 		ev = (CommandEvent*)ckalloc(sizeof(CommandEvent));
 		ev->ev.proc = (Tcl_EventProc*)Tkapp_CommandProc;
@@ -2160,9 +2167,10 @@ Tkapp_DeleteCommand(PyObject *selfptr, PyObject *args)
 		ev->create = 0;
 		ev->name = cmdName;
 		ev->status = &err;
-		ev->done = NULL;
-		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &ev->done, 
+		ev->done = &cond;
+		Tkapp_ThreadSend(self, (Tcl_Event*)ev, &cond, 
 				 &command_mutex);
+		Tcl_ConditionFinalize(&cond);
 	}
 	else {
 		ENTER_TCL