Orca dectalk synthesiser not available

[MICHAEL WEAVER <michaelweaver1 btinternet com>]

some people at my LUG have updated Ubuntu and Orca for me.
They have managed to install Dectalk but we have a problem.
It works when the speech is tested, it works with the Just Say tool.
However, when we ran Orca 0.2.5 which we downloaded from Luke's site for 
some reason Dectalk seems to be unavailable in speech preferences.
Even when we logged off and logged in again and accessed the Orca 
settup, still no option to choose Dectalk.
All I seem to be offered is Gnome Speech.
How do I rectify this problem so I can choose Dectalk?
I am sure it is there from the testing of that synthesiser but Orca 
seems to be treating it like it doesn't exist even though when Ben ran 
the Installation it asked for my registration.