[otrs] Need to add a Chat Button

Hello Team, In the ticket window I want to add a chat button which will activate an external chat client. I was wondering how I can, 1. Add a new button (or link) 2. Include customer chat ID (that can be mapped to customer ID) in the URL Any thoughts? GoodWills   Parag Bhalerao   Work     215-494-2709 Cell        267-210-5949 Email    parag.bhalerao@cybertech.com