#83 Fatel Error

[Zack]

I am using Windows 2000 Advanced Server, IIS5 and
PHP5. I've completed setting the database. Somehow it
still not working. When I try to access issue-tracker, it
just keep showing me Fatal error: Call to undefined
function mysql_connect() in
c:\Inetpub\wwwroot\includes\classes\dbi.class.php on
line 83. How can I fix this? I'm a newbie, so can you
guys help me to fix this, please!