Hello,
I just jump in w/o quoting. I'm that crazy guy who does vimhelp-de.
I use po4a, too. I also noted the issue Omar reports, but it doesn't
bug me to much. My project page is
http://www.florianrehnisch.de/vimhelp/.
The vimhelp is regular utf-8 text, though in a standardized fashion.
Could be worth trying a po4a module. But I'm not that fit in perl. ;-)
flori