This was the subject of horrendous trouble for me a while back. On my old
and new laptops, the argument can be either a string or a [string]. On my
friend's ATI card, however, it MUST be a [string]. It was funny; it took
months to track it down to that. It was my fault really; I had edited it
out in a very early version as it didn't seem to be be necessary...for me
but not for the rest of the world, it turned out.