To properly configure acl, you need to define roles , resources, and permissions .
eg.
$this->addRole(new Zend_Acl_Role('guests')); $this->add(new Zend_Acl_Resource('default')) ->add(new Zend_Acl_REsource('default:index'), 'default'); $this->allow('guests', 'default:index', array('index', 'error'));
This is a module-based structure. So, first you define the role. Then you define the module resource, which is the default. Index - IndexController. And finally, you specify the actions that the guest user must have access to the array.
The second line of code in your question looks fine, so there may be a problem elsewhere. Check out some resources:
Documentation: Zend_Acl
How to do it: Zend Framework 1.8 tutorial 5 zend_acl with zend_auth and a controller plugin
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