[pstricks] trouble with postscript stack

[Jon Joseph]

In the following code I use two definitions of the parametric function.  The only thing I change is the order of the constant multiplier. One works and one generates nonsense.  Is this a bug or something I don't understand about the ps stack?  Thanks. Jon


\documentclass[12pt]{article}
\usepackage[letterpaper,asymmetric=true, total={18cm,22cm}, 
		top=3cm, bindingoffset=1cm]{geometry}
\usepackage[svgnames]{pstricks}
\usepackage{pst-plot,pst-infixplot}
\usepackage{pst-eucl}
\usepackage{pst-fun, pst-coil}
\usepackage{pst-solides3d}



\begin{document}

\begin{pspicture}(-5,5)(5,5)
	\psset{viewpoint=20 5 15, Decran=25, lightsrc=viewpoint}
	
	\defFunction{cone}(u,v) {v Cos 3 mul }{v Sin 2 mul }{u}% <---------------------  Works
	%\defFunction{cone}(u, v){3 v Cos mul}{2 v Sin mul}{u}%  <------------------------  Doesn't work
	
	\psSolid[object=surfaceparametree,
		 base=-2 2 0 2 pi mul, 
		 fillcolor=yellow!50, 
		 incolor=green!50,
		 function=cone, 
		 linewidth=0.5\pslinewidth, 
		 ngrid=25 40]
\end{pspicture}

\end{document}