Automate Office2K installations?

What file do I edit, and specifically what is the syntax, to automatically fill in the product key number during setup? My version of Office2k from my MSDN CD does this. How do I make this happen for my retail version?

For example, with Win98, I can edit the file MSBATCH.INF, create a section called [SETUP] with a line under it reading ProductKey=”11111-11111-11111-11111-11111″ or whatever my CD-key is for Win98 install. Then the number is auto-filled in during install. How do I do this withOffice2k?