Error on DCWorkflow import with cmf.pt (chameleon)

While testing cmf.pt, I had to apply the attached patch to make XML-export & import working with Products.DCWorkflow (on a Plone setup).

I think, my attachment describes the problem pretty well.

1) The first error I got, was missing encoding, which was fixed by defining encoding on the XML template.

2) The second error was caused by missing attributes on the XML. The reason is, I guess, because of the differences in Chameleon's TAL-implementation, boolean values aren't implicitly converted into strings on tal:attributes, but the attributes are just silently dropped. The attributes in question were included on the resulting XML only after I applied explicit transforms from boolen to string using TAL's inline python.

Python 2.6.4
Zope 2.12.14
Products.DCWorkflow 2.2.2

(collective.wtf appearing in tracebacks is used to import workflows described in CSV and makes this problem more apparent, because it first generates XML-export using DCWorkflow's methods and only then asks DCWorkflow to import it, thus this error doesn't appear with working XML-exports, which are hand-crafted or generated without cmf.pt)

2011-01-26 13:37:47 INFO GenericSetup.workflow Workflow tool imported.
2011-01-26 13:37:47 INFO GenericSetup.workflow-csv Updating existing workflow definition simple_publication_workflow.
2011-01-26 13:37:47 ERROR Zope.SiteErrorLog 1296041867.930.658000886015 http://localhost:8081/plone/portal_setup/manage_importSelectedSteps
Traceback (innermost last):
  Module ZPublisher.Publish, line 127, in publish
  Module ZPublisher.mapply, line 77, in mapply
  Module Products.PDBDebugMode.runcall, line 70, in pdb_runcall
  Module ZPublisher.Publish, line 47, in call_object
  Module Products.GenericSetup.tool, line 503, in manage_importSelectedSteps
  Module Products.GenericSetup.tool, line 306, in runImportStepFromProfile
  Module Products.GenericSetup.tool, line 999, in _doRunImportStep
   - __traceback_info__: workflow-csv
  Module collective.wtf.exportimport, line 244, in importCSVWorkflow
  Module collective.wtf.exportimport, line 126, in _importBody
  Module Products.DCWorkflow.exportimport, line 154, in parseWorkflowXML
  Module xml.dom.minidom, line 1928, in parseString
  Module xml.dom.expatbuilder, line 940, in parseString
  Module xml.dom.expatbuilder, line 223, in parseString
LookupError: unknown encoding: None

2011-01-26 13:38:55 INFO GenericSetup.workflow Workflow tool imported.
2011-01-26 13:38:55 INFO GenericSetup.workflow-csv Updating existing workflow definition simple_publication_workflow.
2011-01-26 13:38:55 ERROR Zope.SiteErrorLog 1296041935.890.201639653402 http://localhost:8081/plone/portal_setup/manage_importSelectedSteps
Traceback (innermost last):
  Module ZPublisher.Publish, line 127, in publish
  Module ZPublisher.mapply, line 77, in mapply
  Module Products.PDBDebugMode.runcall, line 70, in pdb_runcall
  Module ZPublisher.Publish, line 47, in call_object
  Module Products.GenericSetup.tool, line 503, in manage_importSelectedSteps
  Module Products.GenericSetup.tool, line 306, in runImportStepFromProfile
  Module Products.GenericSetup.tool, line 999, in _doRunImportStep
   - __traceback_info__: workflow-csv
  Module collective.wtf.exportimport, line 244, in importCSVWorkflow
  Module collective.wtf.exportimport, line 126, in _importBody
  Module Products.DCWorkflow.exportimport, line 170, in parseWorkflowXML
  Module Products.DCWorkflow.exportimport, line 681, in _extractStateNodes
  Module Products.DCWorkflow.exportimport, line 1290, in _getNodeAttributeBoolean
  Module xml.dom.minidom, line 530, in __getitem__
KeyError: 'acquired'