Building website wanders outside DESTDIR

[Pau Amma]

So I decided to try making a minor change to the FreeBSD Handbook myself,
and to test it, I ran (from ~/doc where the raw files live):

% env DESTDIR=/usr/home/pauamma/docobj make all install

This gave me, after a while:

/bin/mv pgpkeyring.txt.tmp pgpkeyring.txt
Warning: Object directory not changed from original
/usr/home/pauamma/doc/share/pgpkeys
===> en_US.ISO8859-1 (install)
===> en_US.ISO8859-1/articles (install)
===> en_US.ISO8859-1/articles/bsdl-gpl (install)
install -C  -o pauamma -g pauamma -m 444 article.html
/usr/home/pauamma/docobj
install -C  -o pauamma -g pauamma -m 444 docbook.css /usr/home/pauamma/docobj
===> en_US.ISO8859-1/articles/building-products (install)
install -C  -o pauamma -g pauamma -m 444 article.html
/usr/home/pauamma/docobj
install -C  -o pauamma -g pauamma -m 444 docbook.css /usr/home/pauamma/docobj
/bin/mkdir -p /usr/home/articles/building-products
mkdir: /usr/home/articles: Permission denied
*** Error code 1

Stop.
make[3]: stopped in
/usr/home/pauamma/doc/en_US.ISO8859-1/articles/building-products
*** Error code 1

Stop.
make[2]: stopped in /usr/home/pauamma/doc/en_US.ISO8859-1/articles
*** Error code 1

Stop.
make[1]: stopped in /usr/home/pauamma/doc/en_US.ISO8859-1
*** Error code 1

Stop.
make: stopped in /usr/home/pauamma/doc

I'm not sure what it thinks it's doing there. Known problem? Pilot error?

This is with revision 53525 (the latest available as I'm writing this) of
https://svn.FreeBSD.org/doc/head. Additional information available upon
request.