The following simple code fails on MacOS X 10.3 running the built-
in python 2.3 and Aqua Tcl/Tk 8.4.9:

import Tkinter
import tkFileDialog

root = Tkinter.Tk()
newPath = tkFileDialog.askopenfilename(
	initialdir = "",
)

The error is:
Traceback (most recent call last):
  File "tkFileDialog_askopen bug.py", line 5, in ?
    newPath = tkFileDialog.askopenfilename(
  File "/System/Library/Frameworks/Python.framework/Versions/2.3/
lib/python2.3/lib-tk/tkFileDialog.py", line 119, in askopenfilename
    return Open(**options).show()
  File "/System/Library/Frameworks/Python.framework/Versions/2.3/
lib/python2.3/lib-tk/tkCommonDialog.py", line 52, in show
    s = w.tk.call(self.command, *w._options(self.options))
_tkinter.TclError: bad directory ""

The same code runs fine on unix Python 2.2.3 with unknown tcl/tk 
and on and unix Python 2.4.1 with tcl/tk 8.4.9. it starts out in the 
user's home directory as I'd expect.

Mind you, I know I can use None or not specify the initialdir 
argument. But in my code it's a string that *might* be empty.

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user_id=2772

At first glance, this appears to be a bug or an incompatible
change in Tk between the old version and Aqua 8.4.9.

If you know the name of the 'wish' executable that uses the
same version of Tcl/Tk as your Python 2.3, please check
whether the tcl command
   tk_getOpenFile -initialdir {}
fails.  If it does, then this is a Tcl/Tk bug or
incompatible change, and I believe this tracker item should
be closed.  Only if that works, but the Python equivalent
doesn't, is there a reason to treat this as a bug in
Python/Tkinter.

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user_id=431773

The suggested tk command does fail:

() 1 % tk_getOpenFile -initialdir {}
bad directory ""

so I'll report this as a Tk bug.

Logged In: YES 
user_id=1188172

Closing this as 3rd party, then.