IDLE warns against an old TCL version even though I've installed a newer version

Question

I have installed ActiveTcl8.6.1.1.297588-macosx10.5-i386-x86_64-threaded on my OS X 10.9.1 . However, when I launch IDLE by running idle3 from the terminal, the following warning shows in the IDLE window:

Python 3.3.3 (v3.3.3:c3896275c0f6, Nov 16 2013, 23:39:35) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "copyright", "credits" or "license()" for more information.
>>> WARNING: The version of Tcl/Tk (8.5.9) in use may be unstable.
Visit http://www.python.org/download/mac/tcltk/ for current information.

Why is the newer ActiveTcl version that I have installed not recognized by IDLE? How can I rectify this?

EDIT: Further details.

$ echo $PATH
/Library/Frameworks/Python.framework/Versions/3.3/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin

$ which tclsh
/usr/bin/tclsh

$ ls -l /usr/bin/tclsh*
lrwxr-xr-x  1 root  wheel  17 Jan 15 10:45 /usr/bin/tclsh -> /usr/bin/tclsh8.6
lrwxr-xr-x  1 root  wheel  67 Oct 25 19:59 /usr/bin/tclsh8.4 -> ../../System/Library/Frameworks/Tcl.framework/Versions/8.4/tclsh8.4
lrwxr-xr-x  1 root  wheel  67 Oct 25 19:59 /usr/bin/tclsh8.5 -> ../../System/Library/Frameworks/Tcl.framework/Versions/8.5/tclsh8.5
lrwxr-xr-x  1 root  wheel  23 Jan 15 10:45 /usr/bin/tclsh8.6 -> /usr/local/bin/tclsh8.6

$ ls -l /usr/local/bin/tclsh*
lrwxr-xr-x  1 root  admin      8 Jan 15 10:40 /usr/local/bin/tclsh -> tclsh8.6
-rwxr-xr-x  1 root  admin  41716 Oct 27 04:45 /usr/local/bin/tclsh8.6

Answer 1

According to the "How Python Chooses Which Tk Library To Use" section of the "IDLE and tinter with Tcl/Tk on Mac OS X" page on the official python website,

The Python for Mac OS X installers downloaded from this website dynamically link at runtime to Tcl/Tk Mac OS X frameworks. The Tcl/Tk major version is determined when the installer is created and cannot be overridden. The Python 64-bit/32-bit Mac OS X installers for Python 3.4.x, 3.3.x, 3.2.x, and 2.7.x dynamically link to Tcl/Tk 8.5 frameworks.

So it seems that

1. The current python installations for OS X do not recognize the latest ActiveTcl version (namely 8.6).
2. The Tcl/Tk version used by python is hard-wired during the python installation procedure and cannot be changed later.

From these observation the solution is clear:

1. Install the latest 8.5 ActiveTcl version.
2. Reinstall python.

I have followed these steps and now everything seems to work.