live support chat system - using PHP/AJAX (jQuery)

Requirement is for a fully functional web based live support chat system. If you have already developed such system then please provide a demo link. If not, you may still bid, however already developed systems will have a preference. Some features we expect: -One to One Text Chat with WebSite Visitors -One Support Operator can Accept Multiple Chat Request -No Visitor Log-in or Sign-up Required - however they will require to enter their name. -Pre-written or Standardized Responses (for quick responses) -Smilies (Emoticons) during chat -File Transfer during chat -Multiple Support Operators Sharing Chat Session -Users (not visitors) to have an image associated to their profile for use in the chat. -Facebook style chat window -Links to web pages can be embedded in the chat text