[Zope] regex vs ts_regex

Apropos http://www.zope.org/Documentation/How-To/ThreadSafety Am I missing something here? There seem to be a number of places in the current 2.2.4 source where the python regex module is used - not ts_regex, thus apparently violating your advice on thread safety? For example, I was just spelunking through /lib/python/AccessControl/User.py, App/Product.py so I started greping a few subdirectories. DateTime.py uses ts_regex as does OFS/ObjectManager.py but NOT OFS/SimpleItem.py ... Is there some reason why it's ok for some modules to use regex rather than ts_regex ??? (I'm resending this to zope@zope.org because it bounced from zopedev@zope.org - is something broken?)