plot2d question



Does anyone know why this example doesn't work?

(%i1) x : [1,2,3,4]$

(%i2) plot2d([discrete,x,x],[style,[points,4,1,6],[lines,1,2]])

It produces only points (of the correct style), but no 
lines.  If I remove the "[points ...]", the lines appear.  I 
see this behavior with both 5.16.3 and 5.17.1.

						Kostas