1. A method for updating a Concatenative Text-To-Speech (CTTS) system with a speech database from a base version to a new version of a given target application, comprising: identifying segments of recorded speech, comprising segments of natural speech; dissecting the recorded speech into a plurality of synthesis units, wherein speech is synthesized by the CTTS system by a concatenation and modification of the synthesis units using a base speech database that comprises a base plurality of context classes derived from the base text; determining a new text corpus subset not completely covered by the base speech database, wherein the new text corpus is associated with a target application; creating new context classes for the target application based upon context classes derived from the base text; and automatically adapting the base speech database for the target application using the new context classes.