sage, can't run command at notebook

I have some Python scripts and I need to run them under notebook.

I run the scripts in %Sage -python <scriptname>.py. It works fine If I run it under sage shell by execfile('/foo/bar.py'). It works fine as well

But if I run execfile('/foo/bar.py') in Sage Notebook, it complains about

...cannot open shared object file: No such file or directory

It appears to me that the notebook can't find the lib. Does Sage and SageNB uses a separate Library-path and Run-path?