I have a new app I'll be working on where I have to generate a Word document that contains tables, graphs, a table of contents and text. What's a good API to use for this? How sure are you that it supports graphs, ToCs, and tables? What are some hidden gotcha's in using them?

Some clarifications:

• I can't output a PDF, they want a Word doc.
• They're using MS Word 2003 (or 2007), not OpenOffice
• Application is running on *nix app-server

It'd be nice if I could start with a template doc and just fill in some spaces with tables, graphs, etc.

Thanks for the help.

Edit: Several good answers below, each with their own faults as far as my current situation. Hard to pick a "final answer" from them. Think I'll leave it open, and hope for better solutions to be created.

Edit: The OpenOffice UNO project does seem to be closest to what I asked for. While POI is certainly more mainstream, it's too immature for what I want.