Content Management System

I need a content management system creating for a diary system for members of staff. It needs to have an internet based log in system for staff to be able to log on from anywhere to enter appointments for clients, by using an individual user name and password.

A calendar would be required to take the user to a particular date. The length of the appointment will vary and if at all possible it would be useful to have three different colour options for the various types of appointments. I have attached an Excel document for reference, that we currently use, but it is not user friendly for Blackberry or other mobiles.

I would like to be able to set passwords and user names locally as and when required.

I am open to suggestions with regard the layout and

Although, I do not have a particular deadline for the completed job, I would be grateful for proposals for an estimated time frame.