gnuplot options& emacs-maxima



I find that emacs gets confused with set of gnuplot options divided by 
semicolon. Say "C-c C-c" at line 
plot3d(x^2*y^2, [x,-5,5], [y,-5,5], [gnuplot_pm3d,true], [gnuplot_preamble, 
"set pm3d at s; unset surf; unset colorbox"])$
does not work for me. The problem is due to diversified ";".
Within console everything's ok. Even it is ok when I just copy the line to 
maxima-buffer inside emacs. I use the cvs version of maxima for cmucl-19a.

rgds,
Valery