/usr/pkgsrc/meta-pkgs/modular-xorg*
A few complications... First -- you have to put X11_TYPE=modular
into /etc/mk.conf. Second -- you'll have to rebuild *all* packages
that use X. Third -- you'll have to adjust a few paths, not just the
default but also XAuthLocation in /etc/ssh/*config. I don't recall if
anything else has to be changed, but I wouldn't be surprised.
--Steve Bellovin, http://www.cs.columbia.edu/~smb
Sounds like it's easier to make a clean install with the ready packages from the net.