[Zope] import paths

I am trying to create an external method in Zope that links to a method in a Python script called "db." The Python script "db" imports another Python script I created called "GDAC". Both Python scripts are located in the Zope site's Extensions directory. When I try to save the changes on the external method I get an import error saying that it cannot find module "GDAC." Should GDAC be located in a different directory? What is the search path for imports within Zope? NOTE: This script works fine in PythonWin. Thanks, Garth