[Zope] Zope 2.7.0 and custom_zodb.py

[John E. Barham]

I'm running 2.7.0 on Linux (Mandrake) with Python 2.3.4.

I wanted to bump up the database connection pool limit so put the following
custom_zodb.py in the instance home:

import os
import ZODB.FileStorage
import ZODB.DB

filename = os.path.join(INSTANCE_HOME, 'var', 'Data.fs')
Storage = ZODB.FileStorage.FileStorage(filename)
DB = ZODB.DB(Storage, pool_size=20, cache_size=2000)

Zope starts fine w/ this (inasmuch as it creates a custom_zodb.pyc file) but
the problem is that when I try to manage the database from the ZMI, it
throws an exception complaining about not being able to lock the database.

I've read elsewhere the using custom_zodb.py is deprecated by the new
zope.conf file in Zope 2.7, but is there a way to specify the database
connection pool size in zope.conf?

TIA,

    John