project - to develop a HELP DESK solution using ASP.NET

Hi,
 I've been assigned a new project - to develop a HELP DESK solution using ASP.NET  which includes:
 - incidents management (tracking tickets)
- forums & chat capabilities
- webmail
- user management (admin, managers, users, etc...)
I've been searching the web and have found endless proprietary products. Although I have a "limited" budget (not to say "zero" budget) I'm all for spending a few 100US$ on a solution that would get me up and running... with some (if not all) of the funtionalities mentioned above. The problem is that i cannot find any FREE or proprietary HELP DESK solutions that include source code. Can any one suggest a solution that incudes some (if not all) of the features i've listed above.
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