ZopeTestCase - "ZopeTestCase is an attempt to make writing unit and regression tests in Zope a more rewarding experience. The package deals with all the plumbing required, and leaves the coder with writing the tests - and the tests only. It is built on PythonUnit and the Testing package coming with Zope." [ZopeTestCase is a more recent product than ZUnit.]
ZUnit [http://zunit.sourceforge.net/] is a Zope add-on based on PythonUnit. It supports testing in a live zope environment. [Not much activity for some months.]
DtmlUnit(does not appear to be available on-line) there is no as such automated tool to test dtml
Zope Unit