"Default Take" with unity engine, after fbx export from blender 2.58

Good day all,

for a start, thanks to anybody reading this, hopefully you can help me solve this dilemma.

I am a new blender user who successfully followed several basic animation tutorials.
Simply put, I have a single-mesh model correctly parented to its armature, which I have very simply animated in two different actions, through (supposedly) proper use of the dopesheet’s action editor.

PROBLEM:
I created the file in blender 2.49. When I export in FBX format, and import into unity, I see the mesh and the two actions, which is what i would expect.
however,
If I open the same file with blender 2.58 and export in the same way into a different filename, when I import into unity, I see an ADDITIONAL animation named “Default Take”. wtf is that? is it supposed to be there? if not, how do i get rid of it? I need to clear this doubt before I go forward with my project.

The file is in the attachment.
untitled249.blend (177 KB)

thanks for the help.