The version that you are using will have little intricacies to it, but I am including some code suggestions that can be customized by using the TDMAIL tags from within the open test architecture manual. You would need to insert the code either specified for certain modules within their respective workflow entities or it could be possible to create a generalized subroutine and then call it from from the after post section of the workflow. You could then create a basic idea/ template and utilizing selection statements (case, if, etc) decide how to present and customize the email. The included code is only a basic idea and would need more customization:
Sub SendDefect (iObjectId, strTo, strCc, strSubject, strComment) On Error Resume Next
Dim objBugFactory, objBug
Set objBugFactory = TDConnection.BugFactory
Set objBug = objBugFactory.Item(iObjectId)
objBug.Mail strTo, strCc, 2, strSubject, strComment Set objBug = Nothing
Set objBugFactory = Nothing
On Error GoTo 0
The constant 2 within obj.mail statement refers to the history being included, this is where you would need to address the individual needs through the OTA TDMAIL tags references to customize the settings.
I hope this gets you started on the path.