[racket] Program works OK in DrRacket, not as an executable

I've pushed a repair for the executable-creation bug.

At Mon, 16 Jul 2012 07:03:17 +0300, Jussi Salmela wrote:
> An interesting (?) fact is the size difference between the last one and the
> other resulting exes:
> 5.1              8 978 KB
> 5.2              8 239 KB
> 5.2.1           8 748 KB
> 5.3.0.13   11 716 KB

I see similar results on my machine (64-bit Mac OS X), but 5.3.0.14 is
back to the old size; I think the problem was the one that Matthias
suggests.