Mod_python error: "PythonHandler mod_python.publisher"

Traceback (most recent call last):

  File "/usr/lib/python2.4/site-packages/mod_python/apache.py", line 299, in HandlerDispatch
    result = object(req)

  File "/usr/lib/python2.4/site-packages/mod_python/publisher.py", line 213, in handler
    published = publish_object(req, object)

  File "/usr/lib/python2.4/site-packages/mod_python/publisher.py", line 412, in publish_object
    return publish_object(req,util.apply_fs_data(object, req.form, req=req))

  File "/usr/lib/python2.4/site-packages/mod_python/util.py", line 439, in apply_fs_data
    return object(**args)

  File "/var/www/vhosts/jameswarwick/lib/eccocms/controller/index.py", line 199, in view_item
    return action.finish()

  File "/var/www/vhosts/jameswarwick/lib/eccocms/EccoViewAction.py", line 251, in finish
    return EccoAction.finish(self)

  File "/var/www/vhosts/jameswarwick/lib/eccocms/EccoAction.py", line 269, in finish
    return Action.finish(self)

  File "/var/www/vhosts/jameswarwick/lib/bright/Webapp2.py", line 399, in finish
    html = str(t)

  File "/var/lib/python-support/python2.4/Cheetah/Template.py", line 989, in __str__
    def __str__(self): return getattr(self, mainMethName)()

  File "_var_www_vhosts_jameswarwick_lib_application_view_ecco_galleryitem_tmpl.py", line 527, in respond

IndexError: list index out of range