Bug reporting System

Hi, I am looking at presenting a proposal for integrating a bug reporting system into our webpage to our management staff. I was wondering the following about the system you have on php.net: What system you use? Is it a custom job? Is the source available (other than using the view source button on every page)? What licences would it fall under? What system do you have for deveopers to login? If the source is available, would you mind sending me an archive that I could use to base a system for us out of? If it is not available, could you recommend an open source project that I could use as a presentation basis? Thanks in advance for any help you can provide. / Martin Noreke