COnverting existing html into docbook/xml ?

Hi,

Currently I try to move existing content to docbook, and I wonder if
there is a way to convert existing html pages into something that
resembles as closely as possible docbook xml.

The idea is to simplify my task of cleaning up/transforming to db
as much as possible.

I am not looking for something fancy or perfect, but just want to get
the rough document structure right, without starting everything right
from the beginning, if possible.

Thanks,
  Marc Baaden