You need recent KDE libs (CVS)

I've just put together a doxygen configuration file. Put it in your local
copy of Umbrello CVS code next the to the AUTHORS file.

You also have to create a directory ../apidocs/umbrello/html and
../apidocs/umbrello/latex. Create a new file (just touch it)
../apidocs/umbrello/umbrello.tag. Also you will need a symlink
../apidocs/common pointing to $KDEDIR/share/doc/HTML/en/common

Then go back to root of source tree and just type doxygen. There will be
several warnings but you will get a good overview on Umbrello. Ah ok, and
maybe you can fix the warnings ;-)