Live Chat and Ticket System

I am looking for a private Online Live Chat software for our systems support business. The following are the features; 1. It should be a registration based live chat system accessible only to our registered clients 2. It should retain history of all the chats that take place 3. It should allow for conferencing to allow many people to chat at once 4. It should allow internal team chat meetings 5. It should be on a secure platform and be on our website Ticket System 1. It should allow clients to log in service request 2. Clients should receive ticket confirmation 3. It should send service request to our technicians by email 4. It should que jobs and record time job is outstanding 5. It should categorise jobs according to Extremely Urgent; Urgent; Moderate and Normal I will only consider bids from providers who have undertaken similar work with references that I can check with. Payment will be through Escrow and released only after succesful completion of job and delivery of system, source code and documentation. Only providers able to deliver within 5 days will be considered.