Find me a PHP Calendaring tool

Thank you for taking the time to look this over! Please note that this bid is for advice, not development or installation (although I may later recruit you to perform the install/config). I need you to help me find the right calendar tool for a PHP/MySql website I am developing. Here is the flow of events: 1. A visitor to the website fills in a form requesting that an event be added to the calendar. An email is sent to an administrator notifying them of the request. 2. An administrator receives the email, clicks a link, and gets sent to a page where he can approve, reject, and/or edit the event. He should also be able to mark the event as "pending", meaning that he has looked at it but is not ready to approve it just yet. 3. The visitor who originally requested the event receives an email notifying them of the acceptance or rejection. 4. Approved events are put on the public calendar (where administrators can continue to edit or delete them). 5. The look-and-feel of the public calendar should be somewhat customizable (colors at the very least, if not layout). The administrators who will be managing the calendar understand CSS but not PHP. ## Deliverables I'm seeking a list of PHP/MySql apps which meet the stated requirements. Preference will be given to those who can provide a concise description of each apps capabilities, and/or a link to a demo/screenshots. There should be very little or no custom code here. An open-source, free tool is desirable, but one-time-cost application is OK (no subscription services, please). ## Platform PHP on MySql