On the Okada Design Blog there's a recent tutorial posted showing you how to create a simple calendar system by combining the CodeIgniter PHP framework and jQuery for some of the client side features.
This blog inspired me to make an event calendar using CodeIgniter. You can download Bari's source files. Please unzip it and save them. We are going to use them later. Bari puts a demo here. We are going to add this to CodeIgniter. I continue using BackendPro for this purpose.