ps.map in linux

I am running the grass4.1 binaries from topquark with the slackware
distribution of linux. I have run up against a problem with ps.map.
At the first try at execution, it produces the error "floating point
exception". The command executes at the second attempt, but
in the postscript output file all raster
levels are assigned the color of the first level. Vectors, titles,and
colortables are created as expected. Has anyone noticed this problem,
or have a solution for it?

  I run GRASS under SCO (that's a PC386 UNIX) (using mostly SCO's
  cc rather than gcc)
  and I've had a couple of spurious floating point exceptions
  in GRASS programs (like adding two FP numbers such as 17 and 21...).
  I've finally decided to catch and ignore that signal in these
  programs (e.g. s.surf.tps). Not a very nice thing to do, but I
  couldn't think of anything else.
  Since you're probably using similar hardware, maybe you have a
  similar problem? But then, ps.map works fine over here...

  Martin