Try
memory_limit = 128M
in php.ini. Your syntax may be wrong.
You can run a function called phpinfo to see what kind of memory allocation you really have. Make a plain text file and call it phpinfo.php and put just this line in it:
<?php phpinfo(); ?>
then put the file in the root of your server, and then go to that file with your web browser, i.e. mydomain.com/phpinfo.php
You’l see all the php info you need; scroll down for memory settings. If you get an error, that means your web hosting company won’t allow phpinfo to run for security reasons.
But that will tell you what the real memory settings are and if your host is being honest. If they are, ask them how to bump memory for your account. If you only see a memory limit of 40 megs, than you’re not able to change it due to their restrictions.