[newbie] problem producing pslatex output-file



I'm trying to produce a pslatex-file of a graph which plots fine on the 
screen but I don't get the file. This is the command I'm using:
wxplot2d([db],[f,20,2e6],[logx],[gnuplot_term,'pslatex],[gnuplot_preamble,"set mxtics 10; set mytics 5;set grid xtics mxtics ytics mytics;"],[gnuplot_out_file,"acl0.tex"]);

I'm using wxMaxima 0.8.5 and Gnuplot 4.4 patch level 2

thanks in advance

hugo