Recently I reported 2 problems related to metapost usage:

1. the loss of transparent color handling

2. textext not being able to handle %'s as in textext("15\%")

The source of both problems can be nailed down to the one change in supp-mps.tex:

\ifx\TEXEXECcommand \undefined \def\TEXEXECcommand{texmfstart texexec} \fi

If I understand correctly, this effectuates a change from the perl to the ruby scripts.

Removing the texmfstart solves the problem.

I compared two runs for the transparency problem in order to see if there is some clue:

1. Both mp-files turn out being the same (except for the random seed).

2. The mpgraph.1 files differ only slightly, except for a few roundoff differences:

new format extra lines: (but not a problem, I would guess)

%%MetaPostSpecials: 2.0 123 1000

%%HiResBoundingBox: -5.66927 -5.66927 359.9991 119.05481

%%MetaPostSpecial: 7 1 1 1 1 0.94118 1 3

I had in my .bashrc:

CONTEXT_RUBYSCRIPTS=/usr/local/teTeX/share/texmf-local/scripts/context/ruby/

export CONTEXT_RUBYSCRIPTS

and had CONTEXT_RUBYSCRIPTS in my path.

Carefully had the executable and read-allowance bits set on all the ruby scripts.

I guess it must have something to do with the ruby scripts, probably MacOSX unique, I fear.

Something done differently with regard to the perl scripts perhaps?

Taco already hinted at the possibility of some end-of-line problem. Alas, my knowledge of ruby is nonexistent, so I have no idea what and where to look for.

I tried hard to find a solution, but I really have no firm idea what could cause these problems.

Hans van der Meer