You should contact Technibraille (http://www.technibraille.com/anglais/accueil.htm) in France. They design operator consoles for blind people (Mainly Alcatel, Ericsson, Lucent, Matra). I don't know if they have a release of their product for call manager, but they are able to adapt their product to a new PBX or LAN PBX in less than one month. I've already worked with them in my previous job for a PBX manufacturer, and was really happy.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.