Problem while trying to register function

[todstoychev]

I' ve used the example from the twiggy page and here what i've got:
Fatal error: Uncaught exception 'LogicException' with message 'Unable to add function "phpversion" as extensions have already been initialized.' in /var/www/Dutchblue/sparks/Twiggy/0.8.5/vendor/Twig/lib/Twig/Environment.php on line 946 LogicException: Unable to add function "phpversion" as extensions have already been initialized. in /var/www/Dutchblue/sparks/Twiggy/0.8.5/vendor/Twig/lib/Twig/Environment.php on line 946 Call Stack: 0.0001 134232 1. {main}() /var/www/Dutchblue/index.php:0 0.0003 135724 2. require_once('/var/www/Dutchblue/system/core/CodeIgniter.php') /var/www/Dutchblue/index.php:211 0.0452 746816 3. call_user_func_array:{/var/www/Dutchblue/system/core/CodeIgniter.php:359}() /var/www/Dutchblue/system/core/CodeIgniter.php:359 0.0452 746908 4. Index_page->index() /var/www/Dutchblue/system/core/CodeIgniter.php:359 0.0452 746964 5. Twiggy->register_function() /var/www/Dutchblue/dutchblue/controllers/index_page.php:5 0.0457 755616 6. Twig_Environment->addFunction() /var/www/Dutchblue/sparks/Twiggy/0.8.5/libraries/Twiggy.php:282