> >   You cannot create a package tar ball without installing the package
> > first.  However, you can set LOCALBASE to something other than your
> > usual installation location (/usr/pkg, by default).  This should at
> > least work for non-X11 packages.  For X11 packages you'd have to change
> > X11BASE, but for this to work, you probably need a full X11 installation
> > there first.
> Yes , but the real problem is in /var/db/pkg which is used to check
> if the package already exists. Setting LOCALBASE does not change this
> behaviour. 

If you want to put the "database" files somewhere other than /var/db/pkg,
set the environment variable: PKG_DBDIR. I know some people who keep all
their "database" files under ${LOCALBASE}. Each to their own.
 
> cross compilation of packages is maybe a bit difficult if you
> insist on installing before making the tarball.

pkgsrc is not set up for cross-compilation - most of the GNU
configure scripts make a wild attempt to guess whether cross-compilation
is taking place, but the configure scripts themselves make far too
many assumptions about the host machine. I wouldn't like to think
what imake would do if it was handed something for cross-compilation.
pkgsrc itself makes a few assumptions which it probably shouldn't.

Regards,
Alistair