Meaning of "Not a directory"

[Marcus Calhoun-Lopez]

I am experimenting with a local version of graphviz.
During the activation phase, I get the error:
Error: Target org.macports.activate returned: Not a directory

Does anyone know the meaning of this error?

The previous message is
DEBUG: Adding link to file_map: /opt/local/Library/Frameworks/ 
Python.framework/Versions/2.5/lib/python2.5/site-packages/gv.py for:  
graphviz

The file gv.py is the problem.
I have arranged it so that gv.py is the only python file to be  
installed.
When I prevent  it from being installed, there is no problem
Strangely enough, the file gv.py does in fact get installed (and then  
the activation phase dies).

The directory  /opt/local/Library/Frameworks/Python.framework/Versions/ 
2.5/lib/python2.5 is not a directory.
It is a link to /opt/local/lib/python2.5.

Any help would be appreciated.

-Marcus