There is a bug in the timelog example in the docs.
Your new time 
fields won't work (but will be displayed)
if you are creating a new 
issue. Change the lines:

      <tal:block 
tal:condition="not:context/id">
        <input type="hidden" 
name=":action" value="new">
        <input type="submit" 
name="submit" value="Submit New Issue">
      
</tal:block>

to read:

      <tal:block 
tal:condition="not:context/id">
        <input type="hidden" 
name=":action" value="new_with_timelog">
        <input 
type="submit" name="submit" value="Submit New Issue">
      
</tal:block>

and associate the new_with_timelog action 
with the
timeLogEditAction routine. In the 
timeLogEditAction
routine, replace the lines:

 # punt to 
the normal edit action
        return 
self.editItemAction()

with:

 # punt to the normal edit 
or new action
 if self.nodeid:
            return 
self.editItemAction()
        else:
            return 
self.newItemAction()

-- rouilj