Before you start, let's make sure you have gnome docutils installed:
Get the package:
http://www.linuxfromscratch.org/blfs/view/cvs/gnome/gnome-doc-utils.html
Install GNOME Doc Utils (this part is borrowed from LinuxFromScratch book)
./configure --prefix=$(pkg-config --variable=prefix ORBit-2.0) --mandir=$(pkg-config --variable=prefix ORBit-2.0)/share/man make
Test it
make check
and then install as root:
make install
switch to Dropbox installation folder
cd /nautilus-dropbox-0.6.3
./configure