I work in localhost
I ried with 'α' and 'Α' but I still got the same problem.
Can you paste the whole source of the alphaindex with the modification?
I used this
<?php $options = $Routes->alphaindex('Α','Α',$directory,array('class'=>'jrButton','style'=>'display: inline;','rel'=>'nofollow'));?>
becuase your code was just print echo $Routes->alphaindex('α','α',$directory,array('style'=>'width:2em;','rel'=>'nofollow')); above buttons