I've done this many times:
sudo aptitude install php5-mcrypt sudo apache2ctl restart
aptitude says mcrypt is installed. I've reinstalled it 3 times already. I've restarted apache about 20 times since I installed it. When I look at phpInfo, I do not see mcrypt listed. When I try to execute my code it says the mcrypt function (pick one - any one) does not exist. mcrypt is clearly not enabled.
Does anyone have any idea what could be wrong? I do not know which pieces should be where and how all this is supposed to fit together.
I installed PHP 5.5.3