Use of this plugin will enable visitors to write their comment in Indian languages (Hindi, Tamil, Telugu, Kannada, Malayalam and Arabic)
transliteration means rewriting in a different script. For example, if you write 'ram' and Hindi transliteration is enabled then after pressing space key or enter key (in other words, on completion of the word) - the text 'ram' will automatically gets converted into 'राम'.
It means your computer does not have support for indian languages. Check wikipedia for details.
For any question/feedback/suggestion leave a comment on the plugin homepage.