Blender 2.58 does not open up when asset is double clicked in Project View

According to the Unity 3D manual, we are supposed to be able to launch Blender to edit our Blender created mesh assets by double clicking the asset in Unity’s Project View tab. I quote:

Updating Assets

You have imported, instantiated, and
linked your asset to a Prefab. Now
when you want to edit your source
asset, just double-click it from the
Project View. The appropriate
application will launch, and you can
make any changes you want. When you’re
done updating it, just Save it. Then,
when you switch back to Unity, the
update will be detected, and the asset
will be re-imported. The asset’s link
to the Prefab will also be maintained.
So the effect you will see is that
your Prefab will update. That’s all
you have to know to update assets.
Just open it and save!

I researched why this doesn’t work and came across this February 2011 question/answer:

Difficulties editing Blender files after importing

The concluding answer by Jessy stated:

This problem is temporary - a result of Blender being in beta. Use 2.49 and switch to 2.5x beta when you don’t have to export to FBX anymore.

Now we are in August and Blender 2.58 stable is out. We are out of Alpha and Beta stages and the ability to launch Blender with a double click on the Unity asset is still broken.

When will this problem be fixed?

Is there a work around that makes sense and works?

Jessy’s solution did not work for me. I used Blender 2.49b to export a mesh .fbx to my Unity project’s asset folder. I imported it into the Unity scene fine but when I double clicked on the mesh in Project View, Blender 2.58 or 2.49b never opened.

You double-click on .blend files, or a mesh defined in those files, not on unrelated meshes or FBX assets.

Double-clicking to edit has always worked. Only the import has been variable, and we’ve always managed to get each new version of Blender to import.