[Wine] Unity3D works. .blend import doesn't

[delirus]

Unity3D seems to be working in wine fairly well, despite a few non-critical problems.  

One such problem is that when a .blend is imported, Unity complains with "Blender could not be found" and instructs me to "Make sure that Blender is installed and the .blend file has Blender as its 'Open with' application!"
I installed the windows version of Blender in wine (first 2.49, then 2.57), and no luck.

I've narrowed the problem down to the certainty that I need to do *something* to the wine registry, but wine seems to handle default applications/filetypes somewhat differently that Vista.

To anyone interested enough to read this far, please let me know if I left out anything in my description of the problem that could help to solve it.

Thanks