Tinymce.html example is giving me an error

[flik]

I was checking http://localhost/jquery-spellchecker-demo/tinymce.html

I am getting the error in firebug console, under the request response of :
http://localhost/jquery-spellchecker-demo/webservices/php/SpellChecker.php

Response:
Fatal error: Call to undefined function SpellChecker\Driver\pspell_new() in /home/ashfaq/public_html/jquery-spellchecker-demo/webservices/php/SpellChecker/Driver/Pspell.php on line 25

I am using php version:
PHP 5.5.21-1+deb.sury.org~precise+2 (cli) (built: Jan 26 2015 20:02:58)
OS Linux ubuntu