Ajax Instant Messenger like the chat on facebook

I am looking for someone to code a Ajax Chat, a bit like the facebook one. I found this Open Source version at: [login to view URL] and I would be more than happy for you to use this to code my project with, but there are lots of people saying it is full of bugs and doesnt work. I would require it to be bug free. The project is for a social networking site: [login to view URL] - Feel free to check it out. The whole site is coded by me and I use no CMS. I am using a VPS to host the site on, so I can install software on the server to help the chat run. I would like this to be done as soon as possible.