In both Docbook 2 and Docbook 5 the toc element documenation says:
"In real life, tocs are usually generated automatically by the presentation system and never have to be represented explicitly in the document source."
So the next question is, which presentation system are you using?
Since you're using FOP (which I haven't used too much), I get the impression from
this documentation that you can just pass
generate.toc=nop on the command line to suppress building a table of contents. See also this
Google groups page.