From EZP Knowledge Base

Packages allow you to specify how much drive space, bandwidth, the number of sub-domains, MySQL databases, the cPanel theme and server other parameters provided to the domain accounts using the package. For our Virtual Hosting clients, when you signed up with EZP, your initial domain is created on the server and given the package you paid for. You can then login to WHM and create your own packages. Every domain you wish to add requires a Package to be chosen when creating the account. To create a package, you need to follow these steps:

• Login to WHM!
• Click the Packages Icon.

• Click Add Packages.

• Set your Package Name and the Parameters you wish for the Package.
• Click the "Add" button at the bottom of the screen.

And that's it! It's quite easy.