Attempting to support PEX

I'm having a lot of trouble getting my plugin to notice the PermissionsEx plugin. I followed the instructions on the wiki for it:

Code:

if (pm.isPluginEnabled("PermissionsEx"))
        {
            permissions = PermissionsEx.getPermissionManager();
            usepermsex = true;
            System.out.println(ptag + " Using PermissionsEx.");
        }

But it doesn't detect PermissionsEx. Am I doing something wrong? This code is from the onEnable method, near the end.

 

Add the line
softdepend: [PermissionsEx]
to your plugin.yml.
The reason why PermissionsEx might not be detected is because your plugin might load before PermissionsEx does, thus it is not enabled yet. Adding a depend in your plugin makes it load after the depending plugins.