It would be nice if the binary installer supported both Tk 8.4 and Tk 8.5: the former is present on all current versions of OSX as part of the system, the latter is the only one that is supported in 64-bit code on OSX  10.6.

A number of Tkinter users have also mentioned that they would much prefer to target Tk 8.5 due to a large number of bugfixes in that version (on OSX).

What I'm thinking of is:

have _tkinter.py that does:

try:
   from _tkinter85 import *
except ImportError:
   from _tkinter84 import *

Then patch setup.py to build _tkinter84.so and _tkinter85.so from _tkinter.c while linking to the right version of Tk. This should only be done when a special configure argument is present, if it isn't setup.py should default to building _tkinter.so like it currently does. 

I don't have time to work on a patch myself.

Workaround for this request: build your own copy of _tkinter when you want to use Tk 8.5 (or later) and use sys.path manipulation to ensure that that copy is used.

We talked about this at the language summit at EuroPython 2010. We'll resolve the installer issue by moving the 64-bit capable installer to Tk 8.5 (with a minimal OSX version of 10.6). 

The 32-bit installer will still use Tk 8.4 because it needs to run on OSX 10.3.9 and later, and that's they only version of Tk that is available everywhere as part of a system install.

I'm closing this issue because the proposed mechanism would only be truly useful as part of the OSX installer and that won't happen.