Quick Tip: If you only see some question marks…

… this could be a PHP Unicode setting.
Try to turn off detect_unicode in your php.ini.
You can simply try this by running n98-magerun like this:

$> php -d detect_unicode=Off n98-magerun.phar

If question marks are gone the problem is solved.

The PHP issue also affects some popular tools like composer or phpunit.
Settings can be persisted in php.ini or you can create an alias on your system.

http://stackoverflow.com/questions/15216292/not-able-to-run-composer-phar