A frequently requested feature from tablet pc users in vertical markets was support for custom dictionaries (medical, field specific, etc). Unfortunately, support for custom dictionaries is not in Vista, but is available in Windows 7. Now, a user can have a primary and custom dictionary for each input scope ( dictionary,country name, surname, etc). In addition, the custom dictionary can take precedence over the primary dictionary. Custom dictionaries can only be created for a language where a recognizer for that language has been installed.
Information on creating custom dictionaries can be found on Microsoft’s WinHEC White Paper site. Download the Touch_Tab_Enhance.docx file and head to page 10. In addition, there is information on doing server-side recognition and installing custom / primary dictionaries on a server to allow recognition over the web via Silverlight, etc.