Broken Product upon installation

Stephen,

System: Zope 2.5.0 (binary release, python 2.1, linux2-x86), python
2.1.2, linux2
Python Version: 2.1.2 (#1, Jan 25 2002, 13:17:56) [GCC 2.7.2.3]
Formulator Version: 1.1.0

After installation and re-boot, I get the following traceback in the
Control Panel for the product:

Traceback (most recent call last):
  File "/usr/local/zope/dev250/lib/python/OFS/Application.py", line 531,
in import_product
    product=__import__(pname, global_dict, global_dict, silly)
  File
"/usr/local/zope/dev250/lib/python/Products/ZMailman/__init__.py", line
7, in ?
    from Products.ZMailman import MailmanFolder
  File
"/usr/local/zope/dev250/lib/python/Products/ZMailman/MailmanFolder.py",
line 13, in ?
    from ListManager   import ListManager
  File
"/usr/local/zope/dev250/lib/python/Products/ZMailman/ListManager.py",
line 1, in ?
    from ZMailList import ZMailList
  File
"/usr/local/zope/dev250/lib/python/Products/ZMailman/ZMailList.py", line
6, in ?
    from FormManager import FormManager
  File
"/usr/local/zope/dev250/lib/python/Products/ZMailman/FormManager.py",
line 4, in ?
    from Mailman import mm_cfg
ImportError: No module named Mailman


What do I need to get ZMailman up and running.

Thanks in advance...

Eric