[mod_python] Trouble importing files through mod_python

Greetings,

We're having a bit of a time importing modules that aren't in the
standard library while using mod_python on this particular server.  We
have had, however, success with other servers.  We're trying to run a
tiny application that looks like this:


on the console side:
~/scratch/
          RunImportTest.py
          __init__.py
          ImportTest/
                     ImportTest.py
                     __init__.py


...and the web side:
/home/httpd/html/beta/
                      RunImportTestModPython.py


Below, the contents of the three files:

RunImportTest.py:
=================
from ImportTest.ImportTest import TEST_CONSTANT

print TEST_CONSTANT


RunImportTestModPython.py:
==========================
from mod_python import apache
from ImportTest.ImportTest import TEST_CONSTANT

def handler(req):
    req.content_type = 'text/plain'
    req.write(TEST_CONSTANT)
    return apache.OK


ImportTest/ImportTest.py:
=========================
TEST_CONSTANT = "success"


Output from the import test from command line:
~/scratch> python RunImportTest.py
success

So we know the little program does indeed work.  Here is the output
from Apache via mod_python:

========================
MOD_PYTHON ERROR

ProcessId:      18704
Interpreter:    'beta.company.com'

ServerName:     'beta.company.com'
DocumentRoot:   '/home/httpd/html/beta'

URI:            '/RunImportTestModPython.py'
Location:       None
Directory:      '/home/httpd/html/beta/'
Filename:       '/home/httpd/html/beta/RunImportTestModPython.py'
PathInfo:       ''

Phase:          'PythonHandler'
Handler:        'RunImportTestModPython'

Traceback (most recent call last):

  File "/usr/local/lib/python2.5/site-packages/mod_python/importer.py",
line 1537, in HandlerDispatch
    default=default_handler, arg=req, silent=hlist.silent)

  File "/usr/local/lib/python2.5/site-packages/mod_python/importer.py",
line 1202, in _process_target
    module = import_module(module_name, path=path)

  File "/usr/local/lib/python2.5/site-packages/mod_python/importer.py",
line 296, in import_module
    log, import_path)

  File "/usr/local/lib/python2.5/site-packages/mod_python/importer.py",
line 680, in import_module
    execfile(file, module.__dict__)

  File "/home/httpd/html/beta/RunImportTestModPython.py", line 2, in <module>
    from ImportTest.ImportTest import TEST_CONSTANT

ImportError: No module named ImportTest.ImportTest


MODULE CACHE DETAILS

Accessed:       Mon Jun  2 14:21:49 2008
Generation:     0

_mp_df6c4429391f4fb65dc56704a2c1e0e2 {
  FileName:     '/home/httpd/html/beta/RunImportTestModPython.py'
  Instance:     1 [IMPORT]
  Generation:   0 [ERROR]
  Modified:     Mon Jun  2 11:49:11 2008
}


...and here's an .htaccess file we're using in the directory
/home/httpd/html/beta, the directory that RunImportTestModPython.py is
in:
=========================
Options Indexes FollowSymLinks MultiViews
AddHandler mod_python .py
PythonDebug On
PythonHandler RunImportTestModPython
PythonAutoReload On
PythonPath "['/home/me/scratch', '/home/me/scratch/ImportTest',
'/usr/lib/python2.5/', '/usr/lib/python2.5/lib-dynload/',
'/usr/lib/python2.5/site-packages/']"


...where /home/me is the user directory referenced at the top of the message.

It's quite likely we're overlooking something very simple--but this
same setup works without hitch on another system (granted, versions of
OS, Apache, mod_python and Python are slightly different...).  This
non-functioning setup is:

* CentOS 5
* Apache 2.2.8
* PHP 5.2.6
* Python 2.5.2
* mod_python 3.3.1
* cx_oracle 4.3.3

some of those are kind of irrelevant for the specific application
here, but there might be hidden conflicts that I'm not aware of. I
have read some stuff about using mod_python's native import methods,
and I'd very much like to use the standard python import method
instead, as it preserves command-line execution without having to add
a lot of overhead.  And in fact, I shouldn't have to because this
setup works on another server.  Unfortunately, I can't simply use the
other server...

Hope this isn't all too much information--I'm very grateful for any
help anyone may provide.

many thanks,
MC