The postscript device behaves strangely - is this possibly a bug?

case 1)

  postscript("gfx-%d.ps",width=8 , height=5, paper="special", 
horizontal=F, onefile=FALSE);
  <some plots here>
  dev.off()

  The first plot is in "portrait" orientation
  The second and all the following plots are in "landscape" orientation

case 2)

  postscript("gfx-%d.ps",width=8 , height=5, paper="special", 
horizontal=T, onefile=FALSE);
  <some plots here>
  dev.off()

  Now, all plots are in "portrait"...

So it seems that the orientation of the *first* plot is not affected by 
horizontal=T/F.

Pascal