Can no longer install ports

[Jim Hatfield]

When I do a make install in any ports dir, I now get this:

>speyburn# cd /usr/ports/graphics/tiff
>speyburn# make
>speyburn# make install
>===>  Installing for tiff-3.5.7_1
>===>   tiff-3.5.7_1 depends on shared library: jpeg.9 - found
>===>   Generating temporary packing list
>===>  Checking if graphics/tiff already installed
>*** Error code 1
>
>Stop in /usr/ports/graphics/tiff.

make deinstall generates the same error.

I tried make -d A but the output was voluminous, to say
the least.

This coincided with strange problems doing portupgrades, 
where I would end up with duplicate directories in /var/db/pkg,
the duplicate having .tbz or .tgz attached to the directory
name.

A clue as to where to look would be appreciated.