Nautilus file .exe file associations

[NoOp]

Ubuntu 6.06.1 LTS
Nautilus version 2.14.3

On one of my systems in Nautilus I cannot double-click a .exe file and
have it open in Wine, instead I receive the following message:

======
Cannot open somefilename.exe

The filename "somefilename.exe" indicates that this file is of type
"executable". The contents of the file indicate that the file is of type
"DOS/Windows executable". If you open this file, the file might present
a security risk to your system.

Do not open the file unless you created the file yourself, or received
the file from a trusted source. To open the file, rename the file to the
correct extension for "DOS/Windows executable", then open the file
normally. Alternatively, use the Open With menu to choose a specific
application for the file.
======

If I right click on the file, it give me the option of "Open with Text
Editor" and "Open with other applicaton". If I then click on
"Properties" "Open With" Wine Windows Emulator is preselected.

If I right click on the file and "Open with other application" and then
"Use a custom command" and use "wine" (no quotes) as the command the
file runs just fine.

Now here is the odd part; if I rename the extention on the file from
lowercase .exe to uppercase .EXE I can double-click the file in Nautilus
and it will run just fine. Ditto for .EXE to .exe and back. Or change it
 from .exe to .win or any other and it will work just fine. After that,
if I right click on the file it will then show: Open with "Wine Windows
Emulator" and "Open with other applicaton" rather than "Open with Text
Editor".

This is just odd. I do not have the problem on three other identically
configured systems, so I'm thinking that somewhere along the line the
Nautilus file associations has gotten screwed up. Anyone else seen this
behavior in Nautilus, or figured out what is causing this?

Added note: I can use an alternate file browser and double-click with no
problem, so this appears to be Nautilus specific.