1. A method in a specific language, for lexically disambiguating non diacritized words in a text and restoring vowels, said method comprising the steps of: automatically generating, by a lexicon generation sub-system, a domain specific lexicon based on a diacritized training corpus pertaining to a specific domain, including, for each word in the diacritized training corpus: removing the diacritics from the word; obtaining all possible valid vowelization patterns for the word, each vowelization pattern belonging to a different stem; selecting from the obtained vowelization patterns, the vowelization pattern that matches the vowelization pattern of the word before the diacritics have been removed from the word; identifying in a generic lexicon, a stem associated with the vowelization pattern that matches vowelization pattern of the word; and disambiguating, by a lexicon generation sub-system, non diacritized words in a text pertaining to the specific domain and restoring vowels by means of the previously generated domain specific lexicon thereby converting non diacritized words in the text to diacritized words.