[DECtalk] Phoneme Input and /d/

[GUI Access]

Calling all DECtalk experts--anyone fluent in DECtalk phoneme input: 
Is there an official explanation of why you cannot make DECtalk 
pronounce the /d/ phoneme correctly (as in dog, did, do)?  Attempting 
to do so using the 4.3 demo results in what sounds like "dho, dhidh, 
dhog".  For the /dh/ in this sample, think of the first phoneme of 
"those, that, there".

I want to hear what long-time DECtalk users on this list have to say 
about this.  I have a theory of why this is a bug.  Later versions of 
DECtalk have a phoneme called /dz/.  While this is poorly documented, 
it seems to be an allophone of the hard /th/ sound.  I.e.  As in 
wiDth (note the capital 'D'; that's the /dz/ phoneme).

My theory is the 4.3 demo has this phoneme and ends up using it 
whenever a /d/ is desired.  That would explain the /dh/ sound you get 
when attempting to use /d/.

Can anyone confirm/deny/comment?  Ironically a single-byte patch to 
the demo ought to fix this problem.  That's a project for a spare 
afternoon...

GUI Access