plot3d and space curves



Until recently I have been using Maxima 5.18.1, In this I could use plot3d to 
plot curves in 3D by having expr1, expr2, expr3 all as functions of x.

Now I have upgraded to Maxima 5.23.2, plot3d does not seem to have these 
operands.

Could someone explain to me how to plot space curves in 3D?

I have looked at draw biut am no wiser,

Regards, Rob.