Question: How do I export a ps figure without borders?

This may be a bug, or maybe I'm just missing something.  In Maple 11 on both Linux and Windows, the following snippet:

with(plots); with(plottools);
plotsetup(ps,plotoutput="plot.eps",plotoptions="portrait,noborder");
Cube:=cuboid([0,0,0], [1,1,1],color=white):
Line:=line([.1,.9,1],[.9,.1,1],thickness=3,color=black):
Sline1:=line([0,.8,.2],[0,.8,.8],thickness=3,color=black):
Sline2:=line([0,.2,.2],[0,.8,.2],thickness=3,color=black):
Sline3:=line([0,.2,.8],[0,.8,.8],thickness=3,color=black):
Sline4:=line([0,.2,.2],[0,.2,.8],thickness=3,color=black):
Circle:=spacecurve([0.3*cos(t)+1/2,0,0.3*sin(t)+1/2],t=0..2*Pi,thickness=3,color=black):
display(Circle,Line,Sline1,Sline2,Sline3,Sline4,Cube,scaling=constrained,lightmodel=none,orientation=[-130,60]);
 

Should produce a file called "plot.eps" that shows a cube with certain figures on the 3 visible faces.  Despite the presence of the "noborder" command, the plot has a border.  How can I export this figure without the border?

Thanks,

Albert Schueller